| Not really, some concepts might be similar, but the overall theme is different. And the graphics are significantly different. You can't really call them similar in my opinion. As for gameplay Diablo II was a success, and Corum is making it's way up there, but I don't think it will be as successful as Diablo.
It's best to compare WoW to Corum, or any other MMORPG really. | 
