It seems just about everyone missed this one as Kevin Feige has let it be known he included the same Star Wars Easter Egg in each of the Marvel Phase 2 movies.
Speaking with CinemaBlend, Feige said he is a big Star Wars fan and offered:
So is this a spoiler for Ant-Man… not really. I’m obsessed with Star Wars. Who’s not? I’m 40 years old. I’m in the movie business. I went to USC. So I’m obsessed with Star Wars – and it didn’t start out as intentional, but it became intentional, including that beat that you referenced. It sort of happens in every Star Wars movie, but I was sort of looking at it, ‘Okay, is Phase Two our Empire Strikes Back?’ Not really, but tonally things are a little different. Somebody gets their arm cut off in every Phase Two movie. Every single one.
Regarding the Easter Eggs:
Iron Man 3 featured Guy Pearce's character, Aldrich Killian, getting his arm cut off by Tony Stark when he heats up Iron Man's suit and the end of the movie.
Thor 2 features Thor getting his arm "cut off" by Loki.
Captain America 2 features a flashback where Bucky had his own arm cut off when he fell from the train in Captain America: The First Avenger.
James Gunn's Guardians of the Galaxy also had a similar Star Wars Easter Egg with Gamora cutting Groot's arm off (this might be the enigmatic Easter Egg Gunn keeps referring to that he says everyone missed).
Those are the Star Wars Easter Eggs known to date as The Avengers 2 is yet to be released - so be on the look out for someone getting their arm cut off just like Luke Skywalker from Empire Strikes Back.