Over the past two days, I've spent about 12 hours split between the two versions, and I've ended up very disappointed the PS3 game. All the complaints you may have heard -- that it looks faded and blurry, and struggles through its framerate -- are true, and more significant than I've seen in any PS3/360 game in recent memory. The 360 version runs into occasional light framerate issues, but nothing that really affects the game. The PS3 version feels sluggish for the majority of the game -- at least, when put side-by-side with the 360 one.
off topic: bayonetta was originally for 360 only, so the porting team for the ps3 has some serious work to do just to get this on par with the original.