Net neutrality.. well.. basically.. without it, the net as you know it is borked. Pipe providers need to provide JUST a pipe and not give a crap about the traffic on it. Just like the colorado department of transportation should have no say in whether or not I can use the interstate in my car, or if I should have my own special speed limit because I'm not a corporation. ; )

Here's a pretty good sound byte sized summary video illustrating the problem.