[aphexairlines]

Let's make a distinction between the two aspects: Last.fm radio and Audioscrobbler. The data from audioscrobber is listed front and center in your profile as "Recently Listened Tracks," your library, top artists, and top tracks. The iTunes plugin is an audioscrobbler plugin, and yes, that's obviously opt-in. But when you sign up for Last.fm radio and start listening with the web player, it scrobbles your listening habits by default.