The spot is a full minute long and includes all the stuff in the Super Bowl spot, plus some more.  Included in that "more" is Thor snagging a ride on a Quinjet, Hawkeye doing some slo-mo action, more of Manhattan under siege, Robert Downey Jr. having his way with Joss Whedon's playful dialogue, and finally, some extra Hulk action that should leave you smiling.

This movie is only three months from hitting theaters, but there's still a huge amount of heavy lifting in post-production, meaning a lot of unfinished visual effects that a legion of VFX artists are no doubt slaving over whilst pounding down caffeine pills with Red Bull chasers.  Throughout the marketing campaign so far, The Avengers hasn't exhibited a real huge scale, no doubt due to the incomplete effects, and this spot provides the first sense that the adventure will get properly big. 

No reveal of the bad guys, though we get to some fairly nondescript villainous footsoldiers flying around Manhattan, and a bit of dialogue between Tom Hiddleston's Loki and Tony Stark.

Whedon is acting as both writer and director with this, his second directorial feature.  The cast includes Robert Downey Jr., Chris Hemsworth, Scarlett Johansson, Chris Evans, Mark Ruffalo, Jeremy Renner, Clark Gregg, and Cobie Smulders.  Consider buying some Rogue 3D Eyewear before The Avengers arrives in post-converted 3D on May 4th.