It has been confirmed that Jon Favreau will not be returning to direct a third Iron Man film, after Vulture initially broke the news yesterday.
The man who was continually told he was "money" in the classic mid 90s indie, Swingers, made a shitload of it for Marvel when the first two flicks hit paydirt, grossing serious clams worldwide. However, he'll leave work on the final film to a new director, with Tony Stark himself, star Robert Downey Jr. given final say over said helmer.
Favreau has the cracking looking blockbuster Cowboys and Aliens due this summer, while he'll spend his Iron Man time working on The Magic Kingdom for Disney. That's a film version, not the actual ride.