George Clooney and Stacy Keibler

It's so totally on! George Clooney proudly walked Sunday's red carpet at the NYC premiere of his film The Descendants with Stacy Keibler on his arm -- in their very first official premiere together as a couple. George Clooney and Stacy Keibler quietly began dating in late summer after Clooney's split from Elisabetta Canalis.