This Slashdot comment probably summarizes the difference of intent between and BSD and GPL as succinctly as one can. Every person who is unclear about the licence to use in his code, or has been a blind follower (“Should be the right one, because everyone seems to be using it”), should keep this at heart. … when the only two ways to release software are BSD and GPL, the GPL will no longer be necessary, but we are not there.
A recent study found out that 1/5th of all research papers are being abandoned because of conflicts with patent holders. One of the slashdot readers asked why. There was this remarkable answer, which was different than other normal economics drenched answers. We have them because the average American wants to believe in a world where he/she can one day strike it rich by inventing some widely used product. The problem is, the patent system doesn’t really work that way, no matter how much patent supporters pretend it protects powerless inventors.