Actually it was not. The GPU in the PS3 (RSX) was inferior to Xenos by a significant margin. 192 GFLOPS vs 240 GFLOPS. In order to make up for it, developers had to program CELL (which was a nightmare at the time) and use techniques like SPU deferred shading just to make up for the lack in RSX ALU power.
See developer notes on the use of SPU deffered shading for CELL processor for Battlefield 3 and their equivalent on Xenos, the slide claims that although there is no DirectCompute or SPUs on 360, Xenos, unlike RSX, has enough power to crunch ALU.
See slide 70 of Siggraph 2011
So all this nightmare programming was just to make things equal, not necessarily surpass 360. In real world scenarios, multiplatform games on 360 generally outperformed the PS3 counterpart.
So what was the result of all the work put into programming cell? Did it really mean that SPU deferred shading for BF3 would make it superior to the 360 version? or was it simply a necessity given the inferior GPU?
You be the judge with these BF3 comparisons below: