Quinjets! Presumably landing on the Helicarrier.
Iron Man, still in the Mark VI armor
Looks like Loki's leading the alien attack.
Steve Rogers: Captain America. Suited up.
Stark armors up.
Black Widow ready for action.
...with a surprise passenger.
Iron Man in Mark VII armor, note the silver on the thigh plates...
...and the additional rockets on the back.
Here they are, the unnamed villains.
Cap being a gentleman and covering Widow with his shield.
Hawkeye falling from something...
...but still shooting an arrow. Compare to this:
Cap with another explosion.
Nick Fury still believes in heroes.
The Avengers Assemble: Iron Man, Hawkeye, Thor...
Loki. He has an army.
Tony Stark. Black Sabbath shirt...
...and a Hulk. Looks a bit like Mark Ruffalo, too...
The Incredible Flying Hulk!