Here's the first trailer for the next Captain America movie. Unlike a lot of people, I was a fan of The First Avenger, particularly the first hour, and its sequel appears to have improved the franchise with a darker tone and a more serious theme.
Again, I think this trailer shows too much of the film--I wish both the helicarrier crashing and the elevator scene had been kept a secret until release, but at least they didn't reveal (for those who haven't read the comic) the identity of the Winter Soldier. Hint: it's not Captain America.
What I enjoyed the most about First Avenger and will probably enjoy in this film as well is the involvement and growth of S.H.I.E.L.D. characters and Black Widow. It's good to see the introduction of new characters as well: Robert Redford as Alexander Pierce and Anthony Mackie as The Falcon, who could possibly make an appearance in Avengers 2 or even Agents of S.H.I.E.L.D. In the comics, the Falcon has ties to the cosmic cube, Black Panther, the Secret Avengers, and even replaced Steve Rogers as Captain America for a while, so there's a lot that could be done with this character.
Actually, the Black Panther helps design the Falcon's wings; I'd be ecstatic if he had a cameo.