Hello! I'm Kristin Volk in for Rebecca Field with a UPI Entertainment Update on this Tuesday, September 11, 2007. Singer Britney Spears says she's embarrassed by her performance on MTV's Video Music Awards Sunday night. She added that she was quote "just plain nervous." Spears continues to be criticized for that opening act. Spears lip-synched through her latest single, "Gimme More," and didn't move much. In the past, Spears has delivered memorable performances on the VMAs, dancing with a ...