360:
Alan Wake
Fable III
Possibly: Splinter Cell: Conviction
PS3:
God Of War III
Heavy Rain
The Last Guardian
Possibly: Resistance 3
That's all I plan on getting at the moment. I'm not a fan of JRPG's. So for my tastes, the PS3 lineup is looking a bit sweeter.
Also I'm more interested in Sony's motion tech then Natal, so that's another point in it's favour.
I'm also excited by what Media Molecule are working on, it will be 2 years since LBP!