Free Stuff?

I love Mp3 blogs. I've discovered so much new and interesting stuff that I wouldn't come across any other way, Cd's are still relatively expensive (well on my budget anyway)and it's nice to try before you buy. What is the legal position on putting up mp3 tracks on your blog? surely if it generates more sales , Record Companies will be happy. Somehow I expect not!

P.S. Everyone please watch QI on BBC2 / BBC4 (UK) it's one of the few shows to stop the mind rot slowly converting the UK into an homogenous chav/ned whole.

P.P.S. Damn - no new Battlestar Galactica last night!