The Purge 3 officially announced

After two very successful movies, Universal announced their intent to make a third film in The Purge franchise likely to be released in 2015. The film will once again be made by Universal, Platinum Dunes, and Blumhouse and James DeMonaco is returning to write and direct.

I personally didn't like The Purge as I felt the movie basically shit on a great concept, so as a result I didn't go see The Purge: Anarchy. However, I did read and hear from friends that it was a lot better than the first one. The announcement of a third film is really no surprise.
People online are already starting to throw concepts around hoping that this third installment will focus on something other than murder. Seeing that all crime is legal during a purge, hopefully with a third film they will start exploring how participants exercise other crimes to seek revenge and vengeance. Potentials could include robbery, sexual assault, kidnapping, stalking, etc..