Even though the character was based on Eminem, and Universal even threatened to cast the D-town rapper, the role of Wesley in comic book adaptation Wanted has gone to James McAvoy. You may remember him as Mr. Tumnus, the fawn, from The Chronicales of Narnia, but more likely you just remember the "Lazy Sunday" viral video that featured the film.
Wesley was the initially spineless lead protagonist in the brutal and funny comic mini about super-villains successfully taking over the world, scripted by Mark Millar and drawn by J.G. Jones. The series was rife with pop culture references including character analogues for DC villains such as The Joker, Catwoman and Bizarro, and strong likenesses of known celebrities like Eminem and Tommy Lee Jones. In keeping with this trend of casting actors from fantasy films, I think the Tommy Lee Jones character, The Killer, should be played by one of the Wheelers from Return to Oz. Shit-your-pants scary.