Summary: I waited a lot before writing this review because this awesome game is cursed by a really bad netcode implementation, I thought the issues could be fixed but since after 2 months the situation is almost the same I think things are going to remain like that forever. Anyway, let's start with everything else, we will get there eventually. The game is, as was SSFIV AE, one of the best fighting games ever made.
Summary: Should have been a free patch. I already own SFxT and multiple copies of SSF4AE - I'm upset that I had to buy this game again to access these characters. New characters are from SFxT (or use the Cammy model with some tweaks). Hold out for Mega-Super-Duper-Streetfighter IV Turbo Hyper Fighting Champions Edition. Capcom hates its loyal customers.
Summary: This review contains spoilers, click expand to view. I gotta say. Every characters all are epically awesome. Its great that they even added some more of the classic characters to this IV ultra. I truly enjoyed playing this ultra edition of the game. I will still give this a fairly high rating even though it has some bugs.
Summary: The final iteration (allegedly) of Street Fighter 4 is here! Ultra has certain issues with online play, but that will undoubtedly be addressed by Capcom in no-time. Other than that, everything that makes this franchise great is here plus the new chars & stages (although copy-pasted from SFxT), new mechanics and new tweaks. Played it for a few weeks now and the overall impression is most positive. Still the best fighting game out there by far!