I would go with a mix of both beneficial and not why?
*beneficial because if developers actually have skill,time.resources the result of what they can get out of ps3 is amazing like MGS4 for example needs the blu ray space or Uncharted 2 currently best looking console game out that have impressed a lot of game reviewers shows what the cell can do if optimized.
*Not beneficial because the architecture is complicated and needs some learning which results to 3rd part developer having trouble getting their game running on the ps3 also there are small 3rd party groups out there that doesn't have the resource to put in time developing a game for ps3 plus the "cell" is not cheap to manufacture making the ps3 insanely expensive for the mass(launch)
Also the "U2 can be done on 360 easily blah blah blah" not knocking the 360's capabilities but I have been hearing this over and over and over and over and over again back @ MGS4. I want to see a actual game to show this instead of just words 360 has been in the market for 4 years and ps3 is late 1 year yet the improvement on it's exclusives are HUGE.