Re: Easter eggs?
All the talk about the mysterious "Phase Two" is a reference to Kevin Feige's classification of the films. "Iron Man" through "Marvel's The Avengers" was the "Marvel Cinematic Universe Phase One". "Iron Man 3" presumably through "Marvel's The Avengers 2" will be the "Marvel Cinematic Universe: Phase Two".
A little bit of teaser work there throughout the film.
A New Hope The Empire Strikes Back
Revenge of the Sith Return of the Jedi
Carrie/Machete Order: 4 films..Best Narrative Structure Possible
Search your feelings. You know it to be true.