CBS has created an interactive music division to house its 100-plus tune websites, audio streams and mobile applications, including the highly trafficked Last.fm.The move is an attempt to aggregate services that reach an estimated 40 million unique monthly users worldwide. It is also designed to extract more value from Last.fm, which CBS paid $280 million to acquire in 2007. CBS Radio vet David Goodman was named prexy of the unit. He’ll remain based in Gotham, reporting to Neil Ashe, prexy of CBS Interactive and working with CBS Radio topper Dan Mason on monetizing radio and music assets on the Web. “CBS Radio and CBS Interactive have been moving down parallel paths to create a new media structure for the future that capitalizes on our unique strengths,” said Quincy Smith, chief exec of CBS Interactive. CBS is due to report quarterly earnings Thursday. The company’s stock gained nearly 2% Tuesday to close at $7.33. That’s up from the lows near $3 hit early this year, but far from the year-ago level of $25 before the ad slump hammered local TV stations and the broadcast mothership.