You may be wondering just why the trailer to comic book adaptation Wanted seems to bear little relationship to Mark Millar and JG Jones' original, replacing Eminem-esque trainee supervillains and a sub-Fight Club plot with something that looks like a second cousin of The Matrix. The answer is pretty simple: The writers didn't apparently know where the story was going when they started work on the movie, and changed things to keep it closer to what they'd been expecting.
When asked about working on Wanted, writer Derek Haas (who co-wrote the movie with partner Michael Brandt) admitted that they didn't seem to know that the comic was going to be quite so... well, comic-book-y:
We first started working on it when only the first issue of the comic came out, and as the book became crazier and crazier, we tried to keep the script grounded... After the second issue, the comic book left the real world and went into a world where super-villains had rid the world of superheroes. It was sort of a mafia story told against that backdrop. So we kept that tone and dynamic, but kept it mostly in the real world, though we do play with things like physics, so it is still a heightened world. It's something you'll see from the first trailer; it's harder to explain here in print.
Not that they're not proud of the result, calling it "a gigantic, hard-R action movie that we hope will satisfy the comic fans." One reason they're hoping the fans are satisfied is the scoop they reveal earlier in the interview: They've just been signed to write Wanted 2 by an optimistic Universal Studios.