I got this off Brooklynvegan who got it off Boing Boing who got it off a book by Kembrew McLeod and Peter DiCola's Creative License: The Law and Culture of Digital Sampling.
Essentially, and please don't tell Girl Talk this, but the laws governing digital sampling are so outrageous it has essentially killed it. I am sure Prince is overjoyed but I have my doubts.
The first thing that comes to mind is that rap would have suffered a crib death if those laws were in effect. I know there must come a point of ussage. For instance, nobody doubts Puff Daddy owed the Police loyalties for "I'll Be Missing You". But there are worlds of difference between that and scratching 15 seconds of "Living In America".
Here is the link to Boing Boing: