Charlie Demerjian has an excellent editorial over at the Inquirer about the RIAA's history with Internet filesharing networks, from Napster to the Grokster decision. He makes the interesting case that the RIAA might have been better served by continuing to work with the centralized server-based model of Napster, as this would have avoided the decentralization of post-Napster networks like Gnutella.
In the old days, there was one provider, and one repository, one throat to strangle. It was manageable technically if it came down to a technical solution. Instead of allowing that technical solution to blossom, they went the legal route, and lost. In the intervening years, the tech went around them, and they sat still, and possibly regressed.
In other filesharing news, the Wirehog website has gone from "Coming August 25" to "Coming late August" to the current "Coming soon." I hope that the delay means they are working on a Linux client.