"But let's also not forget Weitz's behavior on Golden Compass. On December 15, 2004, Weitz announced his resignation as director of the trilogy, citing the enormous technical challenges of the epic and later admitting he was worried about dissing by the book's fans. After another helmer came on and then walked off, Weitz returned to direct saying he'd done "a lot of growing in the interim". Despite all that, Summit seems willing to put its first valuable franchise in his hands. Not so with Twilight director Catherine Hardwicke who's off the sequel for a whole host of reasons I reported that fall under the "difficult" category. Sexism, anyone?"
Also, the thought of the American Pie guy helming the rest of the Twilight franchise kind of makes my head hurt...
Source: Twilight Sequel Offer From Summit Out to Director Chris Weitz? [Nikki Finke's Deadline Hollywood Daily]