Here is some news about the sequel that I got from Dark Horizons website:
"Wanted" comic creator Mark Millar tells Newsarama that he will be contributing story elements to the upcoming film sequel to "Wanted":
"What I will be doing is providing them with a very small amount of stuff for a story, and that will be used as a basic story that they can build from" he says, "It will be a small outline that can possibly be picked apart and not used - but it will be something exclusively for the second film, and no one will ever really see it."
What will it include? "It will be some of the stuff that we didn't utilize from the first book for the movie - like chapters three and four - there will be some stuff from that, so in the loosest sense it will be based on the book, but only very little."
As for the comic itself, which the first film bared little relation too, Millar says he has no plans to continue or revisit it."
Also this talked about a possible trilogy:
"With the stellar box-office of the uber-violent hit "Wanted" guaranteeing a sequel, Cinema Blend has dropped in this interesting rumor about where the franchise is headed.
The site claims that two more sequels are already being planned out with both James McAvoy and Terrence Stamp a lock to be back.
Flashbacks will also apparently explore the past of Angelina Jolie's Fox character, and allow us to meet the man who trained and recruited her - that person becoming the major villain of the sequels.
The sequels are also said to be going more international with McAvoy's Wesley fighting Fraternity cells all over the world with many of Sloane's peers not too happy with the young assassin."