Right now Fox is trying to milk X-Men franchise as much as possible coming with Wolverine this year and Days of The Future Past in 2014. I think Fox should now try to introduce X-Force on big screen in 90s style.
The reason is Hugh Jackman's wolverine is the most popular thing in X Franchise right now and still there is almost no character development. If a X-Force movie, doesn't matter done right or not, will bring out different side of Wolverine along with bringing a better version of Deadpool too.
I think with Days of Future Past fox will next try to introduce Apocalypse and Cable to the X-Universe along with Mister Sinister and Archangel so X-Force can also follow as an immediate prequel to next X-Men movie.
I have read talks about a New Mutants movie as well but I don't find it much appealing as it contains same taste as rest of X movies. X-Force can go into 90s with Cables, Deadpool, Domino, Wolfsbane and other characters thrown in the mix.
After critical success of Dredd this all can make sense and now when Sentinels are being introduced in DoFP movie there will be a need to a black-ops team to work in shadows solving mutant threats everywhere.