The fun in WoW is working with a team to achieve a goal. Raids were a lot of fun.
Aces High is a pure meritocracy. If you get into the same plane as someone else, the only thing distinguishing the two of you at that point is skill.
WoW is a blend - it's a meritocracy and a geritocracy. Clearly those who've played for awhile have an advantage gear-wise, but Blizzard makes the previous raid tier's gear available easily for casuals/slackers. Thus there's never a massive gaping discrepancy in gear between the best-geared and the worst-geared. The thing that's overlooked though is that WoW is a game that requires quite a bit of know-how (in terms of proper specs, gear usage, swapping out gear and specs for certain fights) and skill in execution. I've seen two players in exactly the same gear do dramatically different amounts of damage; only skill accounts for that difference.
I wholeheartedly agree though that leveling in WoW is a horrible, no good, terrible thing. Yuck. Ugh. Pass.