My feeling is that Google want to do things algorithmically as much as possible as they want to make their ranking formula as all-powerful and scalable as possible. However, this looks like they went out and manually identified a bunch of these networks and slapped them as a warning, like the JCPenney thing. It's a cost effective way for them to send a lot of SEOs running and rejig a lot of rankings, but of course it just perpetuates the cat and mouse game and drives smart people underground where they will just keep doing what they were doing but be harder to detect.
Big Google sting, basically. I don't know what some of you are so mad at Google for, they won this round, fair game. Bring on the next round. What, you were ENTIRELY dependent on BMR?! Really? Tut, tut.