I absolutely loved Peggy Carter - she was hot and competent and kicked ass. I cried when she was talking to Steve as his plane went down.
Nazi Elrond - Hugo Weaving so sounded like Elrond, except with a German accent. It was very distracting.
Howard Stark - I hadn't realized Stark Industries existed before the war. We'll probably never see it (but that's what fic's for) but I really want to know what turned the Howard Stark we saw in the movie into the distant, bitter man he became. And when Steve meets Tony... well that should be interesting. Steve's Howard wasn't the father that Tony knew. More's the pity. And I'm guessing Howard was quite a bit older when Tony was born. If Howard was say, 25, in CA, and Tony's supposed to be early 40s in 2010, so he was around 50 when Tony was born? That last time we see him, not giving up searching for Steve was very poignant.
I'm assuming Redskull was taken away by a bifrost? It sure looked like the same effect in Thor, and Loki did say there were many paths to Asgard. I guess he'll meet up with Loki just in time to wreak havoc in the Avengers.
The energy from the cube Howard was experimenting on - anyone else think that was the element Howard left the clues for Tony to create in IM II?