So I'm considering getting this for Vita. Curious about story/arcade mode. Most reviews say that the plot is negligible. But I've seen youtube clips of CG cutscenes. Are those from the game, or a mini movie by Capcom?
The CG character trailers by Capcom are not in the game for some perverse reason.
The arcade mode has an art panel / voiced intro for each official team, and a 2 minute or so CG ending for each official team (plus a generic ending for non-canonical teams). There's actually a lot of character specific banter after each fight though, when you play as an official team. Plus a rival battle for each team, with a lengthy cut scene before it.
IMO the story is actually quite amusing, and has a lot of well thought out character moments that get pretty specific about the personalities of the cast members. Though some "new" personality traits they give certain characters are bizarre, yet still amusing.
Arcade mode also has a very well done sequence of bosses, with unique visual effects and such when said characters are in boss mode. Capcom and Namco teams each fight bosses from the other side.
Overall, it's just a traditional arcade mode, but it's really rather well produced for such. No epic story mode though, as in some of the more robust present gen fighting games.