http://www.eurogamer.net/articles/face-off-street-fighter-iv-article
and the winner is (no surprise) 360.
UPDATE
(due to people not reading the article and just clicking on videos, i'll quote some part of the article)
The PlayStation 3 version mirrors the coin-op in that it's rendering its visuals without the aid of anti-aliasing, whereas the Xbox 360 code gets the benefit of its more usual 2x multisampling edge smoothing. Both are running at an absolutely rock solid 60 frames-per-second, but it's clear that Capcom has had to nip and tuck the PlayStation 3 version in a number of ways to meet this goal.
We'll go into the differences in more depth in a minute, but the key change is that every single close-up sees the PS3 game dynamically downscale to 1120x630, whereas the Xbox 360 game continues to remain at the full 720p resolution. The combination of no AA, plus the enlarged pixels can result in a few ugly scenes, but in most cases it is barely noticeable - 60fps is maintained, and it's amazing how much a super-smooth refresh rate can hide, especially on a game as fast-moving as this one.
The overall lack of anti-aliasing in the PS3 game is hardly a big deal, as there are few 'jaggies' to be overly concerned about. Only on the bright, open stages such as the Airfield do you ever really become aware of it.
Xbox 360 boasts superior lighting and higher resolution textures on a handful of the backdrops, and the characters have additional self-shadows not seen in the PlayStation 3 game. Speaking of shadows, they're smoother and better defined all-round on Xbox 360 too. Other omissions only found in the PS3 build are somewhat odd too - for example, while mountains are reflected in the water, boats aren't. The waterfall in the night-time jungle scene has an additional specular map completely absent on PlayStation 3. Indeed, the jungle itself is more detailed on the Microsoft console, and blended back on PS3.
RSX can handle 22GB/s of data, but the 7900GS trumps it with double that. This all suggests that Capcom maximised the strengths of the 7900GS and the lack of bandwidth hurts the PS3 conversion. Transparent textures in particular require a ton of bandwidth. On Xbox 360, this isn't really an issue, most likely due to the 10MB of RAM directly connected to the Xenos graphics chip, which as an effective speed of a staggering 256GB/s.
As it is, the most noticeable difference between the two versions has nothing to do with the graphics and is all about the more mundane matter of loading times - eight-to-nine seconds per round on 360, double that on PS3. Thankfully the latter version has a ten-minute optional install weighing in at just 2GB, which brings it into the same ballpark loading time as the 360 version running from disc. It's highly recommended that you do complete the install, as playing online against those who haven't done so can get annoying rather quickly. For its part, NXE's 5.7GB install takes much the same time to complete but has little effect on in-game performance.
