I'm definitely certain that she got tickled by crowd.
http://www.youtube.com/ watch?v=rpxoyaUb7L4&feature=related
Pay attention, besides the fact that she's laughing all the time, there's pretty clear shot at 3:55 of a girl in white and the guy next to her tickling her stomach and sides, girl even stroke her arm down to her armpit at 3:57. Pause at 3:55, in that frame the light is white, and you can clearly see her hand in a grasp position Katy's stomach and Katy laughing. The girl in white tickling her stomach last to 3:41 and then they took of her shoes and while the staff were pulling her out she seemed freaked out like someone tickled her feet esspecialy the right foot as they finally managed to take the shoe off that one, few seconds later she flinched her foot and bursted into laughter and you can see the staff smiling ever since it seemed the tickling begun, as well as the crowd.
If you look her expressions from 3:49 to 3:55 and the crowd around her, especialy position of their hands at the time, you'll be assured. She seemed to be exhausted at the end.
http://www.youtube.com/ watch?v=rpxoyaUb7L4&feature=related
Pay attention, besides the fact that she's laughing all the time, there's pretty clear shot at 3:55 of a girl in white and the guy next to her tickling her stomach and sides, girl even stroke her arm down to her armpit at 3:57. Pause at 3:55, in that frame the light is white, and you can clearly see her hand in a grasp position Katy's stomach and Katy laughing. The girl in white tickling her stomach last to 3:41 and then they took of her shoes and while the staff were pulling her out she seemed freaked out like someone tickled her feet esspecialy the right foot as they finally managed to take the shoe off that one, few seconds later she flinched her foot and bursted into laughter and you can see the staff smiling ever since it seemed the tickling begun, as well as the crowd.
If you look her expressions from 3:49 to 3:55 and the crowd around her, especialy position of their hands at the time, you'll be assured. She seemed to be exhausted at the end.