Justin Bieber's rehearsal was even more fun because it was outdoors, so of course a bunch of onlookers (with high-pitched screams) gathered soon after he started. In typical Biebs fashion, his performance was fun and energetic with lots of frantic girls and a little bit of pop and lockin'. I definitely saw the Usher influence, and he has an amazingly cute surprise near the end that I can't wait for you guys to see. (Full disclosure: I was seriously acting like a 12-year-old when I watched).