> Removing individual links makes sense--if someone filed a DMCA request with Dropbox for a song and it ended up getting removed from my Dropbox as well that would be ridiculous.
Dropbox has a very clear concept of private files and public files. If a DMCA request was issued for a file you're storing in your public folder, I would certainly expect Dropbox to remove all instances of that file in all public folders on all accounts.