And all of this is exactly the reason why more and more P2P programs will be designed to work through "Anonymous" proxies.
This way, all transactions will be randon ( multiple hopping ) from different servers, and only the Proxy's IP address will be registered. Not the actual client's IP address.
So what will happen is that thousands of anonymous (log less) servers will appear, and tracing back to users will be almost impossible (or a nightmare!).
Already, programs like "Earth Station Five"
http://www.earthstation5.com/ use this technology.
-kwag