Look, a bunch of people trying to rewrite history again.
Nope, 360 is easier to develop for because it is more powerful at mostly any metric. Period.
Sony throw a lot of money to the right studio, Naughtydog, to max PS3 capabilities. Microsoft throw that money to Kinect bullshit.
But no one, with a minimal of technical knowledge, would ever say PS3 is better, hardware wise, than 360. Because it isn't.
Get over it and play games.
Not really, no.
PS3 | RSX: 176 Gflops and Cell: 230 Glops, Total 406 Gflops
360 | Xenos: 240 Gflops and CPU: 77 Gflops, Total 317 Glops
PS3 based on raw performance is 28% more powerful than the 360.
The reason the raw performance figures did not line up with multi platform titles is because Cell and the PS3's RSX were notoriously difficult to develop for. Non unified split ram, multiples SPE's, less overall memory to work with etc. The GPU was actually weaker, and could only overcome it piggy backing off some heavy handed Cell SPE usage. Sony first party had the time and development resources to do this, which is why PS3 first party titles are the best looking and most technically impressive last generation.