Current reports have “The Hangover Part III” going into production later this year with an assumed May 2013 release date. Word on the street is some filming in Los Angeles and Vegas, with the brunt of the action going down south-of-the-border in Tijuana, Mexico. (Amsterdam was also a rumored location at one point FYI).
This winter their was word that director Todd Phillips and stars Bradley Cooper, Ed Helms, Zach Galifianakis, and Justin Bartha, were all willing to add one more chapter into the Hangover franchise. Apparently contracts were drawn, and things moved forward. Craig Mazin, who wrote Part II, will also scribe this installment. The producers are promising that III will be less of a cookie-cutter clone than II.
Time will tell, looking forward to it.