Nelly Furtado's "Promiscuous" featuring Timbaland holds firm atop the Billboard Hot 100 for a fourth week. The cut also leads the Pop 100 for a fourth frame but loses its No. 1 grip on the Hot Digital Songs chart, where Gnarls Barkley's "Crazy" rises 2-1. John Mayer's "Waiting on the World to Change" is the Hot 100's top debut at No. 25. More...