As far as I've gotten into it, it appears to be Oblivion warmed up just a bit and deeper than ever before, and for my money, Oblivion was the gold standard of RPGs. I'm having some trouble with it on the PC (it was clearly written for the console and halfheartedly converted -- using the mouse has occasionally locked the entire game up), but if it proves to be half as good as its predecessor, it will be a hell of a good time. (And I had to update my video drivers, but it was overdue.)

I think if you don't get it for the PC, it should be less hassle.