Britney Spears is reeling after rap stars Akon and Common blasted her much-hyped comeback performance at the MTV Video Music Awards in Las Vegas on Sunday (09Sep07). The singer, making her first major public appearance in four years, wore a silver and black sparkly underwear set and knee-high black boots to debut her upcoming single Gimme More. But her critics claimed she looked disinterested and unfit. And her fellow celebrity pals seemed to agree. Speaking backstage after the event, Akon said, "That could have been better. She needed to focus more. She looked nervous and I think the pressure got to her." While Common added, "I think it didn't seem like she wanted to be there. There wasn't any spark, it didn't feel like life was there." There was more bad news for Spears - she also had to weather a withering remark from comedienne Sarah Silverman at the ceremony. She sarcastically remarked, "Was that incredible? Britney Spears. Wow. She is amazing. She is 25-years-old and she's already accomplished everything she's going to accomplish in her life. It's mind blowing."