So I've been playing for about 5 hours and it's really addictive. I'll spend an hour just messing around with a new character in Vs. mode getting use to how he works. I've played through the story with Drake and Spike so far. And put in about a dozen online matches. My initial impressions are that I like characters with swords. lol Even more then the ones with guns. It's easier to rack up combos and fill your gauge quickly. Dante and Spike are awesome for this. I haven't even gotten to over half the roaster yet so there's still a lot more to explore. The stages are amazing as well. I love how you'll be playing in Parappa's dojo and a minute later the MAWLR from Killzone 3 is shooting missiles at you.
My main complaint (and I think it will be most people's too) is that when you're playing story mode, it's narrated with nothing but pictures and voice overs. The only time you see any live action is when you get to your "rival fight" just before the end boss battle. And that's over pretty quick. It would of been awesome if each character had a quick live action intro or something before you started their story. The way it is seems really cheap and just lazy. Luckily the core gameplay is just great and that will keep me coming back. It's not overflowing with content like say Mortal Kombat, but I've been playing all afternoon and have just scratched the surface.
As of right now I would score it an 8/10.