Give him proper credit/blame: Shane Black is more-or-less the architect of the modern day action movie. Written when Black was 23, his script for 1987's "Lethal Weapon" was the first to apply the concept known as the "Wham-o-meter," where some big startling thing happens every 8-pages, thus ensuring you, the happy audience member, remain awake between bouts of carnage.
Specializing in quip-happy protagonists, his snappy screenplays for "The Last Boy Scout" and "The Long Kiss Goodnight" garnered him record-breaking paydays, but at the height of his career he vanished for a decade until emerging to resurrect Robert Downey Jr. with 2005's utterly brilliant "Kiss Kiss Bang Bang."
According to Heat Vision, Downey Jr. may be returning the favor by corralling Mr. Black into the stable of directors to potentially fill Jon Favreau's shoes on "Iron Man 3."
Now that Favs is, to paraphrase "Swingers," too money for the franchise (and he knows it), it's going to take someone with a unique set of tools to give ol' shellhead that extra rocket boost to the next level after "The Avengers."
While talks are still in early stages, Marvel is in discussion with Black to not only direct but use those funny fingers of his to hammer out a script for Tony Stark's next adventure. As Downey has director approval, expect him to play a part in convincing the brass that this is the guy.
Black is a big proponent of action revealing character, as opposed to action for action's sake, and if you're still not convinced he's the guy for the job, rent "Kiss Kiss Bang Bang" (seriously, right now) and check out this great piece he wrote for The Guardian where he scientifically breaks down essential elements of action flicks like it's his job… which it is.