I played it at a pre-launch event about 8 weeks ago and it was a good game, but not a touch on Gears of War for the Xbox 360. I see from the reviews on here ChrisP agrees (5/5 for Gears of War and 3/5 for Resistance).

I'm glad I decided to go for the 360 last year rather than wait for the PS3, the PS3 is no great shakes from my experience with it.

P.S. Will: you could do with tagging Gears of War with the same tag as Resistance (Shooting Games) as they are the competing products in the genre on different consoles.