There should be a fundamental game industry mantra in there: "Don't try to beat Blizzard at their own game. You will lose."

Caveat: Unless you think you can sneak out a Diablo game before Diablo 3 comes out. (Nice one, Torchlight)

That was probably the main thing that killed the game. Personally I loved the RvR aspect of WHO (the few times you actually had enough players from both sides on the same server and in the same zone to actually make a decent fight out of it). Easily the most fun I've had with any MMO game. Had they focused on that and really made that the core of their game, it could have been something great.