I already stumbled across tumblr.com a few years ago, but never knew what to do with another microblogging platform...
But in the last few weeks I've found a few nice tumblr websites, to get the idea behind it.
The clean and clear look of it make you focus on the pictures, statements or videos posted.
There is nothing else that drags your attention away, and that underlines the message of the post.
I discovered Theophilus London's tumblr account last summer and it was quite nice to get an idea of the recordings of his album in Stockholm and literally becoming a part of it:
Exhibit A: Mark Ronson on the keys obviously for THIS
It seems to be an usual habit to put up the intention of the tumblr page right into the title, to maintain the clear and straight forward message of the platform.
Other nice tumblr pages I've found during the last few months were "Kanye + Comics", "Eye on Springfield" and "Chicks with Buscemi Eyes". The last two have not that much to do with music (rather than with eyes), but they are all at least as awesome as Mr. London's tumblr account (OR Scott Mescudi's account, too!!):
Exhibit C: The Simpsons Staffel 6, Folge 12 Homer + Mr Burns
Exhibit D: Paris Hilton Buscemized