The Hangover has grossed over $250 million worldwide, becoming one of the four biggest earners of the year (
Star Trek,
Up and
Transformers 2 were the others) and it's also one of the films that has stayed in the top ten for the longest so far.
In Hollywood terms, this means that a) we'll be seeing a sequel and b) the writers of said film have the godly ability to walk on water and turn everything they touch into gold.
So, naturally, the very next script Jon Lucas and Scott Moore pitched has been picked up straight away and is already in production, with
Fred Claus director David Dobkin attached to direct.
The script is very hush, hush right now, but the only things we do know about it are:
-It's called
Change Up.
-It's a body-swapping comedy.
Let the speculation commence!

Source:
http://www.hollywoodreporter.com/hr/content_display/news/e3i0cdf40bc01587c4160b3914f9bae0f99