This from Collider...
Yesterday we learn that Disney bought Marvel Studios and today we’re learning that Robert Downey Jr. and Jon Favreau will delay “The Avengers” and a potential “Iron Man 3″ to do Alex Kurtzman Roberto Orci, and Damon Lindelof’s adaptation of Fred Van Lente and Andrew Foley’s graphic novel, “Cowboys & Aliens”.
According to The Hollywood Reporter’s Heat Vision Blog Downey and Favreau are reteaming but they’re making “Cowboys & Aliens” their next project. That completely botches a 2012 “Avengers
” because that year is now for “Cowboys & Aliens”. And since Downey is officially signed on for “The Avengers”, it means we’re seeing that in 2014 at the earliest. And if “Iron Man 3″ comes into the picture (and I can’t think of a reason why it wouldn’t) then we’re talking a project slate that hurts my brain to even think about it.
If the title didn’t clue you into the premise, the story is about “what would happen if traditional Old West enemies, cowboys and American Indians, found the prairie attacked by aliens in mid-1800s Arizona,” which is a question that’s vexed historians for decades.