As a side note, when Capcom first made that trailer, Tron Bonne hadn't been confirmed yet. And she was in it. For the most part people were happy (thrilled in a surprisingly large amount of cases) to see her back.
The Intro Movie 3 can be summed up as "Magneto defeats everyone".
In the Intro Movie 4, Mike Haggar tears through a billboard with his bare hands before picking up a lead pipe and walking towards a blazing inferno with Felicia on his back. Oh, and he does this after not moving an inch when Thor's hammer touches down nearby.
And said inferno is being created by a fight between Thor and Dormammu. That's right, Haggar wants in on a fight between a thunder god and a demon lord.
This match-up can finally be realized in Ultimate Marvel vs. Capcom 3, with Ghost Rider being confirmed to join the brawl.
The Hulk's ending shows him and Chris storming the Resident Evil mansion.
Most of all, the Hulk beats the tar out of Nemesis.
Of course, with Nemesis being in Ultimate, you can be sure that he won't go down without a fight.
Chun-Li shows that she isn't intimidated by Kingpin in the slightest in her ending.
Morrigan's ending. Where does a succubus go to relax after a hard day saving the world? The mother of all Bad Guy Bars, of course.
Iron Man's Level 3 super attack. Drags you across the ground, scooping chunks of land in the process, tosses you in the air, then finishes with a giant unibeam from his chest.
Wesker's ending. He captures all of the superheroes to experiment on them.
Chris's ending, where he drags Wesker in front of a court to be punished for his crimes..
With the confirmation of Ultimate Marvel Vs. Capcom 3 came the confirmation that Hawkeye was entering the fray, complete with his Hyper Combo featuring him firing an arrow carrying Ant-Man, who grows full size & smashes into the opponent before turning into Giant Man & stomping the victim into the ground.
Most of the new Capcom side is a CMOA, with fan favorite requests such as Phoenix Wright and Frank West appearing.
While it has since been removed in the Heroes and Heralds update, in this video (about 33:45, give or take) Phoenix Wright gets summoned in as an assist (specifically, using his Press the Witness assist), gets hit with two hypers, and survives.
Frank West's ending involves Mr. Fantastic, knowing about Frank's determination in fighting zombies, asks for his help to exterminate the Marvel Zombies. Then, they proceed enter a dimensional portal to kick some zombie ass.