Well I've played a little bit and I'm really enjoying it
So far the gameplay seems faster than VF4 from my memory (it's been a long time). It does feel pretty much the same, doesn't seem to have much change to the fighting as MadBryan said, granted I liked VF4 but still. The animations seem to flow a little better but also still feel the same at the same time.
The character models look great at times depending on the lighting on a particular level. Sometimes they look a bit like plastic or wax coating on some levels. Cloth and such things are animated very nicely. High level of detail with what looks to be tons of customization for clothing and all that, not too important to me but nice to mess around with.
Backgrounds: some are very impressive like the waterfall background, level where it is raining, etc.. Some are a bit more on the plain side IMO. I don't consider this a groundbreaking graphical game by any means but then again VF4 on the PS2 was one of the uglier fighters so it is refreshing that it looks pretty dam good on some levels. Compared to DOA4 the backgrounds in DOA the 4 win hands down, just seem more alive, though I give VF5 the advantage on character models. Of course they are both completely different art styles (and gameplay styles).
Audio, big thumbs down on the commentary, just annoying IMO. Music also nothing that I really like. Sound effects for punching, kicking and all that seem dated, probably just rehashed from older versions. This seems to be a problem with other fighting games as well. Not sure why they don't put more effort into this area.
Gameplay mode that I really like is the arcade mode
(carried over from VF4) which I'm sure I'll spend quite a bit of time in, quite enjoyable playing a large variety of A.I. styles. To me the bread and butter of the game.
Again, just early impression with such little time spent with the game. I'm happy I bought it. Feels like they made the leap to next gen in graphics quite nicely and pretty much took the safe route in gameplay and didn't change too much.
"Virtua Fighter 5 - An Instant Classic" 5/5 "Outstanding" at Gamespy 
