I'm a PC user who doesn't own either of those consoles.
The PS3 has better hardware than the Xbox360.
"The Todd" has said a few times that they showed Xbox footage because they didn't want people to see the PC version for example, then see the Xbox, which wouldn't look as good, and be disappointed. Rather, they wanted people to look at the Xbox, think that's pretty sweet, then see the PC one and have their minds blown.
For this reason, I'm confident the PS3 version will look better if anything, than the Xbox one.
I doubt there's any other difference.
EDIT: I've read through the thread more and realised I've forgotten a point.
Like many people have said, they may not have bothered making graphics tailor-made to the PS3's specs, so it may look the same, or almost identical to the Xbox version.
I guess my revised point is; It certainly could look better on the PS3, if they put in the dev time (which I hope they didn't.. waste of time really, graphics don't make a game - content does).
I agree with your point of view, everything save one. While it is true that great content is essential to making a fantastic game, graphics are also very important if one expects any game to achieve ultimate greatness. For some, presentation is very important and indeed in these days where outstanding technology provides nearly limitless potential, there is no excuse for neglecting any of the quality which we the gamers deserve and have come to expect from our favourite development teams.
Luckily for us, Bethesda’s Elder Scrolls team being the magnificent group of talented people that they are all of whom seem to pay meticulous attention to the details have left nothing to chance and have indeed covered all the essentials.
No matter which platform Skyrim is plied on, from what I have seen and heard thus far, it will be a great experience; one which will change the way we look at RPGs and will undoubtedly set the bar for future developers who will have to live up to Bethesda’s high standards if they are to amount to anything.