Agree with you, except for the years. I think it's closer to 1-2 REALLY good years. And remember, the 360 was launched one full year ahead of the PS3, so naturally it's going to be ahead, especially since it's an American product.
360 will always lead in the online department, we all know that, but I feel like LIVE and a few exclusives are their only selling points. Their exclusive list really is dwindling. They lost Mass Effect, there will be no more Bungie made Halo games, Epic Games president keeps talking about bringing the Gears series to multiplat status. Exclusives are the #1 way to differentiate yourself from the competition.
The 360 REALLY needs to surprise people at E3 this summer with a few new exclusive games. Last year they showed off Kinect, and that isn't going to win any console wars. Neither is the PS Move. Alan Wake kind of didn't live up to its expectations. They still have Forza 4, which has a good chance to be better than Sony's GT5. Fable, how much longer will Peter Molyneux keep making those? Someone will take over the Halo series, but can they keep the name alive?
Lots of questions I have about the 360, and I can't wait until E3 to see if they're answered.