Some information regarding Iron Man 4 has made its way online.
Of relevance was a question that asked what film they looked forward to seeing, with the Marvel movies that are already known to be coming out listed, but also listed is Iron Man 4.
Check out the image below.
There hasn't been anything official in regards to Iron Man 4 or the return of Robert Downey Jr, who is known to be only signed on for The Avengers 2 and The Avengers 3.
There has been talk of Robert Downey Jr. getting replaced similar to what has been done with James Bond -- meaning no reboot, just a continuation of the character using a new actor.
It's possible Iron Man 4 could already be in development, or Disney is using the survey as a way of gauging interest to greenlight more Iron Man films.