And recent comments from Samuel L. Jackson suggest this might be what happened between the time a Nick Fury solo movie was first idealized and now. Asked whether he felt that doing a solo Nick Fury movie would be necessary for anyone who needs to know more about the character, the actor implied the Fury may not need his own film.
"I think a lot of people know [Nick Fury's story]," Jackson told Coming Soon. "I know him as something else because I've been alive longer than most of the fans that watch the movies. So I know Nick Fury as the World War II veteran and all that stuff. It might be interesting to do [that story] one day, but we find out little bits and pieces about Nick and we're going into 'Captain America 2' in late March."
Not a definitve answer, but that's not like Jackson who declared he was having his own solo movie back in the day with enthusiasm and swagger.