Please allow me to assist. (My idle time reading comic books should somehow serve humanity after all.)
First up, an unknown character appears looking like Col. Klink on steroids, complete with monocle. Seriously? Who wears monocles these days except for Mr. Peanut?
This is Baron Wolfgang Von Strucker. Although his four-color version in the funny pages has tangled with Captain America, Strucker is Nick Fury's nemesis. In the comic book world, Fury and Strucker's grudge match began in World War II. The stories were written in the 1960's, but they took place in the 1940's. Sgt. Fury was in charge of a group called the Howling Commandos. (For the movies, Cap was made the head of the Howling Commandos - recall the scene from the Smithsonian?) Fury and his Howling Commandos had to have an equal foe among the Nazi's. So, Lee and Kirby created Baron Strucker and his Blitzkrieg Squad.
Marvel Comics in the 1960's was always paying attention to what was popular. In the 1960's, World War II stories and James Bond were big draws. So, Marvel updated Sgt. Fury, promoted him to a Colonel and made him an agent of S.H.I.E.L.D. They updated Baron Strucker as well. He became to Fury what Blofeld was to Bond. 007 battled SPECTRE, so Fury took on HYDRA with Strucker at the helm.
Many of you have been wondering what happens next for Fury and S.H.I.E.L.D. in the movies. Remember that Nick Fury (the Samuel L. Jackson version) tells Cap that he's going to Europe. Maybe he's going to walk the earth like Kane on Kung Fu. Maybe he's going to meet people and get into adventures. Maybe he's just going to be a bum. But I think there's a good chance he will run across Baron Strucker. By the way, if you noticed that Fury's tombstone misquoted Ezekiel 25:17, you are right. Ezekiel 25:17 only mentions the "Path of the Righteous Man" in the Tarantino version. It's sort of a twisted version and I don't recommend it for serious study.
I suppose you recognized Loki's wand, the one that killed Agent Coulson in the Avengers. But what about those creepy looking twins in the cages. The young man has a bad case of tremors and the girl is making blocks float in the air. The twins are a brother and sister duo known as Quicksilver and the Scarlet Witch. They are mutants but we can't say that in the movie because 20th Century Fox, not Disney, owns the movie rights to Marvel Mutants. This is where some interesting crossovers with the X-Men movie could have happened, but no super-power imagined can overcome studio production rights.
Quicksilver and the Scarlet Witch, aka Pietro and Wanda Maximoff, started out as adversaries of the X-Men in the 1960's comics. They joined in with Magneto and his "Brotherhood of Evil Mutants," a rather sexist, uncreative, and self-deprecating title for a freedom movement. I mean, come on, if you think you are fighting for mutant rights, should you really call yourselves evil? Maybe it was supposed to be ironic. Later on, Pietro and Wanda learned that Magneto was more than just their boss. He was their father. So Vader of him.
Pietro and Wanda were two of the first three replacements for the second assembly of Avengers in comic book history, unless you count Captain America who replaced the Hulk, but it is questionable if Hulk was ever officially an Avenger. Even if he was, Hulk no like puny Avenger's charter. Quicksilver and Scarlet Witch were selected to be Avengers in issue #16. Who was the third replacement Avenger to join Captain America's team? That would be Hawkeye, but of course in the movies he is already on the team.
Quicksilver and the Scarlet Witch will appear in next year's Avengers 2: Age of Ultron. Production photos are already on the internet. Ultron is one of the Avengers toughest foes. He is an indestructible android. An artificial intelligence that hates humanity. In the comics he is created by Hank Pym; who as Ant-Man was one of the founding members of the Avengers. There is an Ant-Man movie coming in 2015, but this will not be Hank Pym nor will he be the creator of Ultron. A few clues appeared in Winter Soldier that suggest the origin of Ultron. Remember when Cap and Black Widow go to the Apple Store in the mall to download the huge flash drive that Fury gave Cap? Of course you do because that's when Black Widow was getting all "girlfriend" with Cap. Anyway, she said that the flash drive was difficult to hack because of a sophisticated A.I. program. Hmmmmm. Next clue, there was talk of an algorithm that would detect potential threats to HYDRA and eliminate them before they could become a problem. That algorithm was developed by the computer mind of Arnim Zola. If Zola can live in 1970's IBM analog computer tech, then don't you think he can give birth to a 21st century digital consciousness? My guess is that these are indicators of how Ultron will emerge in the Marvel movie world.
The Winter Soldier has also given us the first acknowledgment that there is a Dr. Strange. Agent Sitwell was being interrogated by Cap, Black Widow, and the Falcon, and he mentioned Bruce Banner, whom we know as the Hulk, but he mentioned Stephen Strange. Who is he? In the comics, Stephen Strange is known as Dr. Strange. He was a neurosurgeon whose hands were injured in an auto accident, so he gave up medicine to study the mystic arts. His new profession led to his appointment as the Sorcerer Supreme of earth. How Stephen Strange will emerge in the tech-heavy Marvel Movie-verse is difficult to foresee. Even Asgardians are not magical, they just have super-high-tech.
Before someone pulls my geek card, I do know that this isn't the first cinematic name drop of Dr. Strange. That official credit goes to J. Jonah Jameson's assistant, Hoffman, in Spider-Man 2 (2002). When they were brainstorming a name for Doctor Octopus they had the following dialogue:
J. Jonah Jameson: What are we gonna call this guy?
Hoffman: 'Doctor Octopus'?
J. Jonah Jameson: That's crap.
Hoffman: 'Science Squid'?
J. Jonah Jameson: Crap.
Hoffman: 'Doctor Strange'.
J. Jonah Jameson: That's pretty good.
[Hoffman looks proud]
J. Jonah Jameson: But it's taken! Wait, wait! I got it! 'Doctor Octopus'.
Let's hope that dialogue doesn't give Sony the rights to Dr. Strange, the Avengers need him.
Bruce Banner and Stephen Strange being mentioned together is not necessarily an accident. In the comics, they are partners. Dr. Strange and the Incredible Hulk were part of a super-hero team called the Defenders.