Ickalanda on 02 June 2008
http://www.xfire.com/games/aoc/Age_of_Conan_Hyborian_Adventures/
I know it says number 4 on its page but for some reason CounterStrike:Source is being said as number 5 while actually having more minutes played.
The game still has a long way to go before catching up to WoW, if that will ever happen, but I suppose this is pretty significant as it is currently ahead of Guild Wars.
