I'll defer to you on copyright law when it comes to who owns what, but when it comes to those videos on YouTube, this is exactly the kind of backward thinking I'm talking about.
Sure, those videos technically are a violation of copyright law, but if you look it at that way, you completely miss the entire concept of viral marketing. No you aren't getting paid, but you will make your money indirectly and that's the key to understanding how YouTube can drive sales. If all you do is look at strict adherence to copyright law, you aren't going to get anywhere. Sure, you are technically in the right, but there are lots of people who get that this type of promotion primes the sales pump.
I also get that people are using MySpace and other venues to sell themselves as musicians and recording companies are finding new artists there. As usual, it's the musicians who lead the way and the record companies found them there and have begun copying their successful techniques.
But just as you have done that with this type of marketing, you have to understand the value of those types of YouTube videos. It's not about being paid for these things, it's about driving interest and interest drives sales.
What is happening and is what will continue to happen unless you fast forward to 2009 is that record companies will become increasingly irrelevant. Musicians don't need you to sell their music anymore …