Tumblr's John Maloney and David Karp MySpace's collapse has left one important population in a weird place: Professional musicians, whose MySpace profiles are often their primary web URLs, host samples of their music and tour dates, and -- most importantly -- show up very high in Google.

That's the gist of this post by music manager Caren Kelleher, which we found via Peter Kafka's MediaMemo.

It's obvious that musicians are going to move away from MySpace more slowly than the rest of the world, which jumped to Facebook, Twitter, and other social sites years ago. But when musicians do leave MySpace, where are they going to go?

This is a huge opportunity for Tumblr, which is insanely simple to use for blogging, and could easily handle most musicians' needs with 1) better support for static pages like "tour dates," "bio," etc., and 2) some sort of digital playlist tool for music samples. (Almost like a "Muxtape for Tumblr.")

This is an even more obvious place for Facebook or YouTube -- or even Apple's "Ping" -- to step up.

But as Kelleher reminds us, "I'm weary about sending fans to Facebook since it can change privacy policies, tab layouts and other settings with little or no notice." (She concludes, "And so, we're sort of stuck with MySpace Music, whether we like it or not.")

MySpace is eventually toast -- that much is clear. So who's going to take over as the homepage for the world's musicians?

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