I switched to PS3 permanently in 2009 around the time Infamous came out. That was when I got rid of my 360. The system started firing on all cylinders and Xbox would soon start going downhill in my opinion. Definitely the best system of that generation. Tons of great exclusives, with a ton of variety.
I can't keep stressing it's amazing to see how modern day Sony has fallen so much. They were on a roll with the 3 and 4.
It is, PS3 is the best console of that generation, it started out average but two years later when MGS4, Killzone 2, GOW3 and especially Uncharted 2 started coming out it was an incredible console, Xbox 360 was going to be the best but it sank in 2009 when they started with the Kinect garbage.