Mary-Kate Olsen's Taste in Men Is Superbad

Mary-Kate Olsen is two-timing her boyfriend with a surprising new guy - chubby “Knocked Up” star Jonah Hill, the Enquirer has learned exclusively. The unlikely couple cozied up to one another at Los Angeles’ Chateau Marmont hotel on Aug. 26 - just one night after the stick-thing actress stepped out to a rock concert with steady beau Nate Lowman.

“It was a shock to see Mary-Kate together with, of all people, geeky Jonah,” an eyewitness told The Enquirer. “They were on a double date with another couple, dining at the hotel around 10 p.m. Mary-Kate and Jonah sat close together and seemed totally into each other. They were both wearing plaid shirts that almost matched. It was the cutest thing.”

“From what I saw at the Chateau Marmont,” said another source, “Mary-Kate had forgotten about Nate and seemed totally enamored of Jonah. And he couldn’t keep his eyes off her, either.”