The last few attempted comebacks by Britney Spears have gone through fits and starts, but her latest album undeniably proves she is back. Circus tops the Billboard music charts this week after selling 505,000 copies. Circus is her fifth number one album and makes her the first artist to break the half-million mark in the first week. Oops! I Did It Again still remains her top seller, with 1.3 million sold. If all breakdowns have similar effects on sales, then twenty bucks says Madonna will “accidentally” shave her head by the end of the week.