Mamie Gummer caused quite a stir at last night's Whitney Gala when she casually introduced her date, Ben Walker, to us as her fiancé. A reporter for People magazine duly quizzed the happy couple — apparently they'd only become engaged like two days ago! — and ran home to type up the story, only to find that UsWeekly.com's reporter had apparently gotten to her computer faster and already had the breaking story online. News is a cutthroat business. (Mamie, start a bidding war for those wedding pics stat!) Anyway, before anyone steals our own little scoop, New York wants to tell you that the lovebirds are planning to cross the river and move to Dumbo. "It's, like, right by the city; I mean, it's one stop in, and you get a great bang for your buck," Meryl's daughter tells us. Besides, the actress thinks the neighborhood is a fateful choice for her, because she has an extensive collection of stuffed elephants. "It was from when I was a kid. I just, I had a thing with elephants; I had maybe 60 of them." While the two think Dumbo is awesome, they don't hang out there much yet. "I don't think it's a destination," said Gummer. "I think it's like, you live there and it's a good place to be based, and then you go elsewhere."