The best counter to the more sweeping conclusion is that last.fm users are also very keen to listen to songs by women. The same songs, often. But the initial conclusion - the kind of music listeners are ashamed of is overwhelmingly by women - stands, I think.
Tom’s right; my contention that “Last.fm users can’t bear to let people think they listen to songs by women,” was sloppy and hyperbolic. We’ll stick with the initial conclusion.