First up, in a few brief clips of upcoming Agents of SHIELD episodes we got a glimpse of Adrian Pasdar as Glenn Talbot.
Talbot was Hulk's biggest military rival (other than General Thaddeus "Thunderbolt" Ross) for decades, and his biggest rival for the affections of Betty Ross until his untimely death. Although the specter of his return has been floated in the comics from time to time, his brother Brian Talbot is currently the Gray Hulk (although he hasn't really interacted with the Red Hulk or green Hulk in any major way).
Some Avengers: Age of Ultron scenes were shown, though none with the principal cast. The concept art, however, showed off some cool sneak peaks:
Here we have Hulk fighting Iron Man's Hulkbuster armor. The Hulkbusters were originally a group of people working to take down the Hulk by any means necessary, and despite Iron Man and Hulk both nominally being heroes, Tony Stark has Hulkbuster armor ready for any time the Green Goliath goes on the warpath. To be fair though, Tony's a pretty paranoid guy; he even has Thorbuster armor. (Thanks to SupaChupacabra for the image!)
We also get glimpses of Scarlet Witch and Quicksilver (thanks to KingOfAwesometonia for these images!)
Scarlet Witch, of course, is Magneto's daughter in most versions of the story, but this fact won't be brought up in the Avengers film. There is an out, if the flimmakers so-choose. For many years it was believed that the true parents of Scarlet Witch and Quicksilver were World War II heroes Whizzer and Miss America, and there's no reason this can't be true in the Marvel Cinematic Universe.
Quicksilver is Marvel's most famous speedster, and arguably the fastest runner on Marvel's Earth (though there is a lot of competition for that title). His appearance may confuse some casual audience members, as he'll be an entirely different character from theQuicksilver of X-Men: Days of Future Past, despite the two sharing names and powers.
Over the credits we were treated to a few brief seconds the Ant-Man proof-of-concept footage shown to attendees of Comic-Con 2012.
Speaking for myself, I loved the footage at Comic Con, and I wish Marvel would just officially release it already.
The rest of the special was a great look back, but I do have one gripe: the decision to have the Hulk movie fit thematically with the 1970s Hulk TV series is treated like a great idea. I disagree. This is why the Hulk - while successful - is viewed as the least interesting of the Marvel Cinematic Universe movies by so many fans. Hulk of the comics is a much more fun and dynamic character, even when he's trying to kill himself or just be left alone. The Avengers movie showed an understanding of this, and if they bring back the fun for a Hulk sequel, it could smash the previous film's reputation.
All and all, a fun hour-long advertisement. Here's looking forward to more Marvel movies!