Everquest II is fast approaching another expansion release, this one entitled Rise of Kunark. Their last expansion, also released last November, was absolutely outstanding. If it weren't for WoW and LoTRO, I'm sure I'd still be playing it.
While no MMO comes close to WoW in terms of intense raid content, I do think Everquest II offers more overall content than any other MMO on the market. It's nearly the perfect game for the casual gamer.