In the aftermath of the crushing of Kazaa in Australia, it looks like the RIAA has gathered the confidence to start making threats. The organisation has told seven P2P software companies to sort themselves out – or face dire consequences. The companies are being asked (or told) to shut down their networks or implement RIAA-approved anti-piracy measures.

The RIAA hasn't said which P2P networks it sent cease and desist letters to, but the Wall Street Journal yesterday named LimeWire, BearShare and WinMX, and it's not hard to guess who the others might be.
This comes just a few months since the US Supreme Court ruled that P2P providers Grokster and StreamCast are responsible for the actions of their users. This means that if these companies do nothing to stop their users from committing copyright infringement then the companies themselves are also guilty of this crime.