I disagree. WOW still has a good chunk of hardcore people playing. I'd say the ratio is probably similar to the EQ days.Major difference was that the population of MMORPG players pre-WOW was incredibly small. Post TBC/Wrath it was much larger and much more diverse. Pre-WOW the majority of MMO players were hardcore. Not so much in 2009/10 whatever.
I think comparing then and now hardcore vs casual is absurd. Most EQ players were not hardcore. The vast majority played casually, but the no lifers are often focused on here. For every hardcore guild there were dozens of casual ones who enjoyed the game in moderation. Many of the people who played EQ could actually code and a good chunk had engineering or science degrees and were refugees from Compuserve. Most of those had jobs and lives and weren't the 18 year old hardcore stoners who by and large were the kids of said engineers and scientists that seem to get stereotyped on these boards.
Today with high speed 'net as the norm and the global market being astronomically larger, I doubt the ratio of hardcore vs casual is any different now that the average moron who has no idea how to solder can play any game with his Alienware and the PC world requires no actual technical knowledge. There just are a fuckload more people, which means a ton more subs for Blizzard.
The problem is a lot of sites like this are still focused on the same group of stoner hardcore types who now that they are older have moved into being the dirty casuals that their parents were. That doesn't change the ratio, it just means you grew up. You are now your Dad. Congratulations, or I guess condolences however you want to look at it.