i read an article in the Wall Street Journal about this yesterday. As stated above, those sharing over 1,000 songs are much more likely to be sued. Plus, they cannot sue you for downloading the music! I mean, how did YOU know that it was copyrighted? Now, if you are sharing, YOU are the one who is making copyrighted material available to others, and YOU should know that it's copyrighted if it's yours... So, basically, dont share. Which sucks, because if nobody shares, there will be nothing to download........
-Jason