LimeWire has already the code to start filtering but it is not in the current versions. LimeWire will filter content thought, so we prepared an alternative already so people don't get lost and switch from Gnutella to another network.
LimeWire could die anytime, this won't be the case with FrostWire.
We are happy that you use LW for now, once LW starts filtering, you'll know what to do and tell your friends about it
Ciao