Good idea, and there are others like FILE PASS THROUGH and file rotation on a 24 hour basis that all these developers could easily add to their programs TODAY, right NOW.
So BearShare, Limewire take NOTICE!

You could have saved 17,000 people from getting a notice. How many more have to be DAMAGED because of your lack of motivation to add some simple routines?
Notice that I said that nasty DAMAGE word. As in Damaged Party. Need I say more?

And if you want to keep your "market share", and not have all your users switch to a more PRIVACY ORIENTED file sharing ap like freenet or filetopia, then you have another motivation to do this.