The PS3 has the same drive as any Blu-ray DVD player so the only issues are size and connectivity. I have heard many say PS3 is definitely the way to go because they cost about the same and you can game!!!
Not from what I hear (so to speak). If a PS3 and a Blu-ray DVD player were hooked to the same system in the same manner they will sound exactly the same.
I would think the differences would show up in the functionality such as remote control, the ability to load more than one disc and things like that.
The good thing about the PS3 versus standalones, is that it is upgradeable. So it is pretty much future proof when considering audio and video codecs. It also gets good reviews for it's CD and SACD playback. If you take away the fact that it is a video game console, it is still a silly deal!