Iron Man

[Alex]

Here's what happened after the credits:

Spoiler:

Stark comes home after his press conference and finds somebody in his home.

It is Samuel L. Jackson and he introduces himself as Nick Fury, asks if Stark really thought he was the only superhero and that he is there to talk about the Avenger Initiative.

To people familiar with the comics I imagine this wasn't a huge surprise once Agent Coulson dropped the name S.H.I.E.L.D. combined with the fact that the current design of Nick Fury has been modeled on Jackson for a few years.

To me, who has no real familiarity with Marvel Comics (especially ones more recent than 20 years ago) it was a surprise to see Jackson, but I had no real idea what the scene suggested beyond a sequel.