Jeremy Renner almost made it into Captain America: The Winter Soldier as the writers really wanted to include him and even had some lines in early versions of the scripts with mention of Hawkeye.
However, with Black Widow, Nick Fury, Cap and the Winter Soldier being the focus of the movie, Hawkeye was let go in order to keep the script up to par.
There are rumblings of Captain America 3. I don’t know what’s going to happen there. I’ve got to find the time, man (laughs). I’m trying to stay home and I can’t.
So it sounds like, once again, the writers for Captain America 3 want Hawkeye in the film, but this time maybe it's up to Renner.
Hawkeye and Jeremy Renner will also be featured in next May's The Avengers: Age of Ultron.
New images of Renner as Hawkeye recently hit the net as well.
Captain America 3 has a May 6, 2016 release.