Black Panther is a Marvel Comic character, and his film would be a part of the shared Avengers-Iron Man-Thor universe, so this is pretty much guaranteed to be a big movie.
Chestnut started the rumors when he posted a comic cover on his facebook account with the caption, ‘It’s time to get familiar with the Black Panther character!’
Which could mean anything from ‘I just got the role and have to study up on the character,’ to ‘I just heard about this comic, and I want to see what it’s like.’ But then he followed up today with this tweet: Not final. #BlackPanther may be in #avengers2 first. RT @jamaal91604133: @morris_chestnut Can’t wait to see this movie. #BlackPanther
Still vague, sure; but ‘not final’ implies that there’s something tentative going on. It’s hard to say if the Avengers 2 timeline is an actual plan from Marvel, or wishful thinking on Chestnut’s part.
A Black Panther film has been bandied about for awhile. Wesley Snipes was once attached to star, but jail seems to have squashed that.