Normally the Biggest Loser finale is during the 3rd week of May and with all the Chaos and Drama going on this season the finale was projected to be on May 22, 2012. There is a rumor going around that NBC is shifting the finales this year due to the Olympics. I found a link from NBC that does announce that finale will be May 1st and only one hour long. I am posting it here so as many people as possible will get the information.
NBC Entertainment Press Release
"THE BIGGEST LOSER 13"
05/01/2012 (08:00PM - 09:00PM) (Tuesday) : "THE BIGGEST LOSER" REVEALED IN EXCITING SEASON FINALE – In this must-see, exciting live finale, the contestants from this season return for a special reunion and a chance to weigh in one last time – and show America how much weight they’ve all lost since beginning their weight-loss journeys. Those who have been eliminated will compete for the $100,000 "at home" prize. Then it’s the moment viewers have been waiting for, when one of the three finalists will be named this season’s "Biggest Loser" and win the coveted grand prize of $250,000! Alison Sweeney hosts the series, and trainers Bob Harper and Dolvett Quince also star.