@Two posts above - Not to mention none of their games would fit a controller very well, either. Baldur's Gate Dark Alliance is similar what Diablo would be, and while it was alright, it wasn't what Diablo is. And their other games are RTS games, which we've seen the result of on consoles, and never has it been really good. And lastly, World of Warcraft, which... Well, dunno. Similar to Dragon Age, I suppose, except a lot of networking that I'm not sure consoles can handle. The PS3 might be able to, maybe, with a lot of work, but I don't think the 360 could. But even then, issues with control, probably.
Blizzard games (thus far) are made for the PC.