After playing WoW for 4 years off & on, and playing the Aion open beta, I can say Aion certainly was more impressive to me in a visual way & also that so many of the things you had to get addons for in WoW were actually builtin to the UI of Aion. Aion also seemed to be in a better state during its open beta than WoW was as far as stability, balance, and bugs. But, many in the chats kept on saying, "man, this sucks compared to WoW, so much lag", or insert other complaints. They're comparing a just launching product with one that's been out for several years, not saying they can't do that but it needed to all be put into perspective. That said, WoW has Aion beat hands down in amount of content. And if you're mostly a PVE'r WoW is going to be a better choice. If you're going for PVP, I think Aion makes more sense, WoW's PVP is very watered down. For me, even if I do get into another MMO again, I'm probably waiting for SWTOR. Actually there are several good looking MMO's coming out "soon" (tm) so you may find it better to just wait for now.
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