We've seen Batman LEGO Mini Figures from DC Comics for a while now - seen at San Diego Comic-Con,, the lineup is about to get bigger - along with new Marvel Comics characters to boot! The line-up consists of 6 x DC characters (Batman, Joker, Catwoman, Poison Ivy, Wonder Woman and Superman) and 5 x Marvel characters (Captain America, Thor, Iron Man, Hulk and Wolverine).
The above group-shots are via ActionFigureInsider, while the close-ups belong are via ToyArk.com (original uncropped images via). So did you notice the Hulk LEGO beside Chris "Captain America" Evan's signing at the Avenger's stage at SDCC? (Probably looked better than the Captain America LEGO figure, no doubt ;p). The figures will be released under the banner of "LEGO Super Heroes".