Just found this site a while back and re-found it again, if you guys want to know the *approximate* subscription amount for almost all games, mostly P2P I don't think F2P is in this list, then go there and look at the charts.

It hasn't been updating lately but WoW is lower since china went down under as well as a lot of other details like some of the games like Aion aren't counting from each country. I'm sure older games like Lineage 2/1 and such are fairly accurate though they have an accuracy rating page you can look at to see the sources for their information.

Site : http://www.mmodata.net/

It's pretty neat to see all the ups and downs and approximates on how many people are sub'd to a game.