Oh. I just found this:
Back in May we unveiled our project to build a new version of Last.fm.
Our goal was to lay the foundation for an online music experience more
compelling, accessible, and discoverable than anything that had gone
That was last July. So… not only did they not properly handle duplicate artists, same-name artists, multiple bootstrapping, and handling of classical music in their design… they didn’t take care of it in the redesign.
That’s almost enough to convince me I shouldn’t bother with them, but not quite, I guess.