yeah i'm sure Bearshare is legal because otherwise they wouldn't have had their site up and running for so long. If they were illegal the powers to be would have shut them down.
See, with napster, they actually had the files (music) on their server and were offering the file to the public, whereas other P2P programs act just as the middly guy in transferring files between people. Bearshare has absolutly nothing to do with the files themselves, just the transfer if stuff back and forth to people.