HDUFF050307_01.jpgRumer Willis HDUFF050207_15.jpgBon Jovi had a "Nice Day" on American Idol and was celebrating with a dinner at Mr. Chow! The Duff sisters also ate Chinese last night while Lance Bass partied over in Hollywood. Mischa Barton was rolling to a private party with a new, attractive mystery guy! We caught up with the But Can They Sing? reject, Bai Ling at the Stoli party, where Bai told us she was working on a book. But can she write? Bijou Phillips and Justin Long (who was much tighter-lipped than when we saw him out Tues.) were also at the big bash.