The New York District Court, at the request of the RIAA, has forced Limewire to shut down its network and cease distributing its software.
Limewire has taken down the relay severs on the Gnutella network which the Limewire client uses to figure out which other p2p clients have what info on them.
Unfortunately, this will render existing clients down to nothing more than a sub par media player.
RIP Limewire!