PS3 exclusives are far better than the 360 ones IMO.
The only 360 exclusives i'm interested in is Gears Of War.
I only really use my PS3 for it's exclusives.
I could argue the same about the PS3, i have both but the 360's exclusives work for me.
Killzone ? give me gears any day
LBP i tried, many times, just cant get into it ..
MGS4, didnt like this too much either (too many cut scenes damnit!) but then i never enjoyed them after the first one either.
Uncharted? didnt like as much as Fable.
Resistance? didnt get as many hours as BC2 (yes yes, multi plat) or Halo: Reach probably for that matter.
GT5 or Forza ? Forza held my attention more.
etc etc.
In general the 360 exclusives hold my attention way more, they just appeal to the type of gamer i am so its obvious why my 360 gets pretty much all of my attention.
Others will be in the other camp, and the third type of blind brand loyalty gamer.. well, i wont get started on that one.
-edit-
There's something else which bugs me to hell with the PS3, although its been toned down lately.
Why on earth are all sony exclusives so 'cold'.
Its hard to explain, but graphically .. its like if you take a photo and apply a 20% cooling filter in Photoshop.