Yes, it looks like Big Momma's House 3 is really happening, and director John Whitesell will be making it happen. What did he do to deserve such a fate? Well, he directed Big Momma's House 2, for a start.
It was probably inevitable. The first film made $174m worldwide on a budget of only $30m, while its sequel made a still-decent $138m on a $40m budget. With Martin Lawrence once again expected to don fat suit and wig to play the dual role of Big Momma and FBI agent Malcolm Turner, it'll no doubt be another case where the FBI's finest has to go undercover as a fat old lady in order to protect a beautiful woman, crack open a drug ring and catch the ne'er-do-wells.
Shooting starts in Atlanta in April, so you might want to avoid the city from March, just to be sure.