@Mark, as per usual.
The PS3 has many wonderful things about it. But your pitiful fanboy whining really does exaggerate things too much to retain credibility:
1) "GT5:P makes Forza2 and PGR looks like a joke." Graphically, it's seriously difficult to tell GT5:P and PGR4 apart a lot of the time, unless PGR4 is playing around with its OTT weather effects again, or your screen is big enough to quickly spot GT5:P's native 1080p resolution (not easy, since the antialiasing on PGR4 is better). In terms of handling, GT5:P and Forza 2 are very close; in fact I'd give the edge to Forza unless you're using wheels. And that's possibly more due to Logitech's offering being comfortably better than Microsoft's.
Up until a collision happens, obviously; at that point Forza 2's excellent damage model gets a chance to show how it can affect the handling as a result. Supposedly this is something coming to the 'full' GT5, but then cynical GT veterans can probably remember some of the long list of missing features we've been promised in the past.
Re: Grid, I've not experienced any issues with the 360 one yet. But I've not played it a hell of a lot (still, any play is more than you, I suspect).
Re: "good games", Ninja Gaiden Sigma is really pushing to call an exclusive when it's just XBox Ninja Gaiden with a few bonus bits. Not like the true sequel (which is, oh! 360 exclusive). Still, my friend who has already completed MGS4 twice (perk of being a journo) says it's completely amazing. Not amazing enough to avoid the wrath of hordes of whiny teenagers demaning he be visciously slaughtered for the heresy of not rating it a full 10/10, but still one of the best games he's played this year.