Put me into the "360 version is better" camp. I played the PS3 version all last night, unlocking stuff and messing around. This morning I hooked up my 360 (just moved) and tried the game out, and there is a noticeable difference. The 360 version looks a little better (cleaner picture) and DEFINITELY loads faster (and yes, I installed data on my PS3). It's also nice that you can unlock all the stock characters in like 10 minutes. Unlocking everyone doesn't take that much time either. I'm glad it doesn't take forever; I hate unlocking characters in general but this felt relatively painless. Now to do it again on 360.
Vader is okay I guess. He's better than Yoda, who is just WEIRD. Apprentice seems kinda cool, but I don't want fucking Star Wars characters in Namco fighting games. Sure this is better than Spawn, but not by too much.
I see DLC is already up too. You can buy old songs and some custom parts from the original SC.