Many of us already know that there will be a fourth Rambo movie,
as well as the 6th of Rocky(is this one finished yet?).
Anyway, here are some interesting notes I found at trektoday.com:
April 12, 2006 - 5:44 PM
Avery Brooks (Captain Sisko) will reportedly appear in the new Rambo film - the fourth in the series starring Sylvester Stallone, with this installment also to be directed by the action movie star.
Moviehole reported that Brooks had joined the projection. Other actors in the film will be Bruno Campos as the villain, of Dallas, and Tony Burton, who appeared with Stallone in all of his Rocky movies as well as in Shade.
The part of Rambo's new ally, a U.S fugitive, wrongly accused of war crimes, has not yet been cast, though Lost star Matthew Fox is rumored to be up for the role. The Internet Movie Database has only Stallone listed as confirmed but offers a brief plot summary, "Vietnam vet John Rambo is forced to emerge from his reclusive lifestyle and take justice into his own hands after a girl goes missing."
The movie, which will be filmed on location in Mexico as well as in US studios, was scheduled last October to begin shooting this spring. Stallone is also working on a sixth Rocky film.