I was a heavy 360 gamer till I got my new high end PC. Back then my old PC couldn't even play flash games, Now I'm running Crysis 2 on max settings.
Currently looking forward to the release of Battlefield 3 on PC. Got that pre-ordered can't wait to experience the new frostbite engine.
I'll probably just rent out Modern Warfare 3 on 360 to see what it's like but overall doesn't really interest me looking like a DLC for Modern Warfare 2.