Gwen Stefani rehearsed with her band, No Doubt, yesterday in NYC. Gwen will kick off the upcoming NFL season with a live performance at Rockefeller Center before the reigning Super Bowl champions, the New York Giants, take on the Dallas Cowboys tonight at MetLife Stadium. No Doubt will be joined by Mariah Carey, who is also set to take the stage before the inaugural game of the season. Gwen made a fashionable appearance at LAX with son Kingston for her trek east earlier this week. Gwen and No Doubt have been on a promotional run for their new album, Push and Shove, which is set for release on Sept. 25.