I don't want to and you can't make me!

Cei-U!
I summon the intransigence!

I remember, as a kid, beginning with Batman #437 and naively thinking their were 436 previous issues of consistency and continuity, all building up to that very story. What a glorious fantasy.

Honestly, I just hate trying to keep volumes straight.

"Hey, I've got Green Lantern. #2."

"Which?"

"Ummm...Hal Jordan Green Lantern."

"Which?"

"Ummm...modern age."

"Which?"

"Ummm...Geoff Johns."

"Oh. Which?"

Britain's long running war comic Commando is currently up to #4942. Beano is currently at around #3850, I believe.

DC wins this hands down.

40's:
COMICS: DC creates the superhero, the superhero team and the three most iconic superhero characters (Superman, Batman, Wonder Woman) to Marvel's One (Captain America). Marvel does, however, have a memorable story arc featuring battles between two of their heroes - The Human Torch and the Sub-Mariner.
MEDIA: DC has multiple (mostly forgettable) film serials (Hop Harrigan, Congo Bill, The Vigilante, Batman), a successful radio series (Superman), and a series of amazingly good cartoon shorts (The Fleisher Superman series). Marvel has one largely forgettable serial featuring Captain America.
CULTURE: Impact: Superman is a phenomenon. His radio serial helps bring down the KKK. His catchphrases are household words. Captain America hits the cultural zeitgeist, but is swarmed by a host of similarly patriotic heroes.
OVERALL: DC.

50's:
COMICS: Superman, Batman and Wonder Woman all continue publication. Marvel produces mostly forgettable work.
MEDIA: DC has the hugely successful Superman TV series with George Reeves.
CULTURE: Impact: "Look! Up In The Sky!"... yeah, Superman still rules. Marvel? Who even are they?
OVERALL: DC.

60's:
COMICS: DC launches the Silver Age with the reworked Flash. While inspired by DC's reworked Justice Society, the Fantastic Four from Marvel proves very successful. Spider-Man even moreso. Marvel's young, hep and grounded approach, the showmanship and jazzy presentation of Stan Lee and the unrivalled imaginations of Jack Kirby and Steve Ditko really connect with existing comics readers and college aged kids. Marvel's more raw approach is seen as cool, DC is seen as corny, conventional and staid.
MEDIA: A TV series and feature film based on Batman becomes a global phenomenon. There's a fairly successful Spider-Man cartoon.
CULTURE: College aged kids are drawn to Marvel's characters and approach making comics cool again. On the other hand, Batmania.
OVERALL: Marvel hits it straight out of the gate.

70's:
COMICS: Both companies attempt to diversify. DC has some successes (Sergeant Rock, Jonah Hex, House of Mystery), but too much too fast leads to a catastrophic meltdown. Neal Adams becomes the first 'superstar' creator for DC. Marvel counters with Jim Steranko, P.Craig Russell, Barry Windsor Smith. Marvel's attempts at diversity are more successful, with titles like Man-Thing, Ghost Rider, Tomb of Dracula, Howard the Duck and Master of Kung Fu. Marvel scores two licensing coups in Conan the Barbarian and Star Wars. DC successfully lures Jack Kirby away from Marvel but fails to capitalize. A revitalized version of The Uncanny X-Men proves incredibly successful for Marvel.
MEDIA: DC has a big success in 'Wonder Woman' with Lynda Carter, and the animated series 'The Super Friends', which is popular despite a heavy censorial burden. Marvel has a big success with 'The Incredible Hulk' with Bill Bixby and Lou Ferrigno. The 'Spider-Man' series by contrast is pretty awful.
CULTURE: Marvel's cool factor continues with characters like Conan and the Silver Surfer. Wonder Woman is name-checked by Gloria Steinem and the Women's Lib Movement. Attempts by both companies to consciously tap into cultural movements are mostly done pretty ham-fistedly.
OVERALL: A mixed bag, but Marvel definitely has the edge. DC is increasingly looking desperate for ideas, and trying to play catch-up or unsuccessfully attempting to ape Marvel's winning tactics.

80's:
COMICS: Both companies settle into a kind of holding pattern, with Marvel somewhat ahead. DC has several substantial spikes in experimental titles like 'Dark Knight Returns', and Alan Moore's 'Swamp Thing' and 'Watchmen'. Wolfman & Perez' 'New Teen Titans' mimics the X-Men formula successfully with DC's teenage heroes, and the two creators go on to shake up the DC universe and transform it into something more resembling Marvel's universe in 'Crisis on Infinite Earths'. At Marvel, Archie Goodwin's 'Epic' imprint begins attempting to ape 'Heavy Metal' and ends up bringing manga (Akira), European comics (The works of Moebius), and independent US works (Elfquest) to a wider audience. It's hit-and-miss. John Byrne' having made his name on X-Men, has an extremely succesful run on 'Fantastic Four', until he is wooed away by DC to relaunch 'Superman'.
MEDIA: DC pretty much rules this decade, opening with 1980's 'Superman: The Movie' and ending with 1989's 'Batman'.
CULTURE: Suddenly comics are cool... but for the most part, the comics people are talking about are Indie titles like Cerebus, American Flagg, Love & Rockets, and not necessarily the mainstream monthlies being put out by the 'Big Two'.
OVERALL: The differences between the two companies start to look increasingly cosmetic as both companies mainstream titles are increasingly settled into their respective holding patterns.

90's:
COMICS: Flush from the 'Crisis', DC takes the lead, with superstar creators Byrne, Miller and Perez reworking Superman, Batman and Wonder Woman respectively. The success of Alan Moore on Swamp Thing and Watchmen leads DC editorial to the UK to recruit more British talent and eventually to the creation of the Vertigo imprint. By contrast, Marvel circles the wagons, and seems to be trying to rely on the proven success of their X-Men characters to lift them out of their slump. Both companies, fearing the rise of popular independents, artificially inflate demand for comics and create a speculator bubble with things like Variant Covers, and similar Gimmicks. An attempt to create a new batch of superstars backfires when the superstars leave Marvel and form Image. DC has a massive financial success with their (otherwise intellectually bankrupt) 'Death of Superman' event, while Marvel ACTUALLY goes bankrupt.
MEDIA: Like the Superman films, the Batman films start to run out of steam after the first two installments. A short-lived Flash TV series is well-regarded but not terribly successful. An X-Men Animated Series by Fox Kids becomes widely popular. However, the big news is the Bruce Timm and Paul Dini's 'Batman: The Animated Series' which, drawing on the aesthetic of the old Fleisher Superman Cartoons, revitalizes tv animation in a big way and paves the way for a DC Animated Universe.
CULTURE: Comics are big news, but it's chiefly an illusion, build around false ideas of economic speculation and collectability. Tonnes of unsold copies of 'Superman' #75 and 'X-Force' #1 languish in comic stores and landfills across the world. Everyone's looking for the NEW thing, and increasingly, that's NOT looking like the decades old properties being peddled by Marvel and DC.
OVERALL: DC takes the lead again.

2000's:
COMICS: Under Joe Quesada and Bill Jemas, Marvel attempted to crawl back from bankruptcy. They recruited a host of creators from indie titles, and released some more experimental stuff. Sometimes the experiments worked (X-Statix, Runaways) sometimes they didn't (Tsunami, Marville). DC, meanwhile, in trying to maintain its lead, started repeating its previous successful moves. Killing Superman sold lots of comics? Let's Cripple Batman! Green Lantern Goes Crazy! When these didn't work, they looked back to the start of their success, 'Crisis' and hit the history eraser button. Wash. Rinse. Repeat.
The Vertigo Imprint, on the other hand, was having a lot of success. Titles like Sandman, Preacher, Hellblazer and Transmetropolitan were starting to draw in the sort of crowd that normally read those indie titles that were so encroaching on DC's and Marvel's Market Share. But that didn't stop it from happening. Companies like Dark Horse and Image were beginning to seriously threaten the previously unassailable two-company system.
MEDIA: Marvel finally got out of the gates with Spider-Man and X-Men films which people liked... unfortunately, as with DC's efforts in prior decades, both did really well in their first two installments and then kind of lost their way. An attempt to relaunch Superman by relentlessly aping the earlier films failed to engage audiences, however, oddly enough, a TV series reimagining the character as a high school soap opera managed to do quite well. A gritty reworking of Batman's origin, however, was a major success.
Meanwhile, the DCAU kept merrily trundling along, with a Superman series, two Justice League series and a second, more futuristic version of Batman.
CULTURE: Despite successfully engaging mainstream audiences, successful movies and tv series didn't translate into comics sales. The comics market was widening and diversifying, and in response, both Marvel and DC began increasingly to focus on retaining existing readers rather than acquiring new ones.
OVERALL: DC's maybe a hair ahead at this stage, but it's probably more due to Vertigo than its increasingly stale DC Universe stuff.

2010's:
COMICS: In seeking to gain new audiences, Marvel began pushing outward to try and gain new readers, adopting a similar approach to that used by the Quesada/Jemas team (indie creators, diverse titles). Meanwhile, DC tightened their circle and doubled down on the things which had succeeded before - periodic reboots, and an increased focus on continuity and edgy, 'mature' storytelling. To this end, spin-offs of Watchmen and Dark Knight were both solicited.
MEDIA: DC had a major success with 'The Dark Knight', the follow-up to 'Batman Begins', but Marvel overwhelmed them with a Cinematic Universe, a series of solo films featuring Iron Man, Thor, Captain America and the Hulk and designed to build to The Avengers, and then roll on into a second, and third phase after that. Attempts by DC to license non-superhero films were largely unsuccessful 'Red', 'The Losers', 'Jonah Hex', and their attempts to build a DC Cinematic Universe have been met with a mixed response. They are, however, having some success with the fusion of superhero action and teen-soap, applying the 'Smallville' model to Green Arrow, the Flash, Supergirl and others.
CULTURE: The Marvel Cinematic Universe has turned masses of the mainstream audience into comic book fans, though whether the companies can convert that into comics SALES is another matter. One big concern is whether this current superhero fascination is another bubble, like the speculator bubble of the 90's... and if so, when will it burst?
OVERALL: The MCU had allowed Marvel to take the lead... but to what end?

I agree, though I'd have to give DC the edge for the 80s--while the X-men juggernaut continued to build, I don't see much else from Marvel after Miller leaves DD (except a lot of sales--you got me there. but creatively...)

Also, while Marvel consolidated its fan base, with Vertigo, DC started making "comics for the cool kids." And, again, while they may have tarnished in the past 30 years, Watchmen and Dark Knight are still the high watermarks and general cultural touchstones. (and, hell, look at the recent fuss because Killing Joke was being adapted.)

And while, ultimately, some of the more singular experiments of this time--Nathaniel Dusk, Helix, DC Challenge, lots more, etc.--didn't make much of a lasting change, they showed DC really trying to engage creators. This was also the time they first started to regularly credit artists and writers on the cover of the whole line, right?

Plus the Batman movie....

Frankly, I don't know anything about the 3rd paragraph ... And while, ultimately ... could you please clarify that for me so I can understand what you are saying here?

I'd add that at DC, there were minis like Nathaniel Dusk, Tailgunner Jo, Spanner's Galaxy, others I can't remember right now (what was that Gulacy thing about the aliens reforming Earth?) that weren't part of the DC universe and never would be part of the DC universe. I don't think many of these were very successful commercially or gained DC many new readers, but I didn't see Marvel making similar efforts to grow the market (rather than just trying to grow their share of the market).