I'd say your assumptions of it selling more than Killzone 2 this summer are 100% correct.. Considering Killzone 2 won't be out this summer (or this year perhaps)
If perferring the PS3 over the 360 makes me a fanboy.. I guess I am guilty..
List of 360 Games I would like to have: Alan Wake
List of PS3 Games I would like to have: LBP, FFXIII(if it ever comes), R2(maybe)
List of Wii Games I would like to have: Star Wars: The Force Unleashed (It's not an exclusive but it would be awesome)