Unless I'm missing something, I don't see why anyone would need a separate BD player if they've already got a PS3. This isn't like the old days where magnetic pickups have to read off tapes, and better pickups would result in better quality vid/aud (ie. VCRs).
All the PS3 has to do is take a digital video and digital audio signal, and pass it through to the outputs (assuming the use of HDMI). There's no DACs that would make a difference...
Other than minor differences in remote-menu function, I don't see how the PS3 could be much different from any other player. It supports full 1080p, does it not? Hell, my PS2 would do 1080i on some games, and that things ancient!!! lol