Apparently he's not tired of those mother-f#©king superheros in the mother-f#©king Marvel Universe.
Samuel L. Jackson's Nick Fury has been the common thread connecting Marvel's various superhero movies over the past few years. For a while, though, it was being reported that Mr. Jackson wouldn't be appearing in Captain America; Jackson himself went on Jimmy Fallon back in February and revealed that this was a lie being spread by traitorous rumor-mongers. Now, video and photos have appeared on the Web of Jackson shooting his cameo, thereby providing a couple of spoilers about the film's ending/epilogue.
The scene takes place in a modern day New York City, right in the middle of Times Square. This means that a) the entire movie doesn't take place during World War 2 and b) audiences will get to see Steve Rogers after he's unfrozen. Presumably, this will take place as a kind of post-credits cameo, but Screen Rant has an interesting theory that also seems reasonable:
What an awkward and noisy place to shoot, being surrounded by people in Times Square. Seems like more of a marketing stint than smart shooting location. Note the Acura vehicles surrounding the set -- It's Acura sponsoring the franchise, providing all of the SHIELD rides and sponsoring the viral marketing campaign.
There's another video of the same scene from a different angle, as well as some nice high-resolution photos of Chris Evans running down the street in an S.S.R. shirt ("Strategic Scientific Reserve" was the group responsible for the experiment that gave Steve Rogers his powers).
Source: Screen Rant