The controversy started with the leak of U2's "No Line On The Horizon" last week. The album appeared on file-sharing sites after Universal Music's Australian arm accidentally began selling downloads two weeks early. But on Friday, the technology blog Techcrunch sparked privacy concerns when they posted a rumor claiming that Last.fm, the CBS-owned music streaming and social networking site that allows registered user to keep track over their digital listening habits by "scrobbling" tracks played on computers, MP3s players and other streaming sites, had shared private user data with the RIAA that could identify individuals who had listened to the unreleased U2 tracks.