The reason? She's got too much work to do to, you know, work.
"Christina Aguilera's summer tour has been moved to 2011 due to prior commitments that the singer had made to her film Burlesque and to the promotion of her new album Bionic," tour promoter Live Nation said in a statement.
But don't cry for her busy schedule. She's really canceling it out of respect for the fans—putting on a show now wouldn't live up to the quality either Aguilera or her audience have come to expect.
"The singer felt she needed more time to rehearse the show and with less than a month between the album release and tour date, this wasn't possible," her spokeswoman said.
The tour was scheduled to begin on July 15. Her new album, Bionic, is due out June 8. The new dates will be announced later this year.