Rockstar has released more information and these two screenshots of Max Payne 3 at PAX. If I could write this in slow.... mo.... I.... would.
After getting addicted to painkillers (it's the player's fault, damn it!), Max is no longer the New York cop he used to be. He has taken his Punisher-style vengeance from the Manhattan to Sao Paulo, Brazil, where he becomes a private security guard for the family of Rodrigo Branco and his family.
Max's signature bullet time, however, remains intact, now enhanced by Natural Motion's Euphoria engine and real-time physics. Players can also expect him to activate bullet time just by performing stunts on various set pieces, sometimes right out of cover, as if Max has been spending his spare time playing Vanquish. Bullets can destroy pretty much everything in the environment, creating a bombastic environment that would make John Woo blush.
Taking a page out of Heavy Rain, James McCaffrey will reprise his role as Max not only through voice, but also through his appearance, face, and movements (which will spawn at least several fan-made side-by-side comparisons). Also expect many beads of sweat and blood to capture the gritty gunplay.