This Reason.tv video illustrates the weak case for network neutrality regulation of Internet service providers.
In the AT&T case, which the video touches on, an AT&T web site blocked some (barely) controversial statements by Eddie Vedder---the Pearl Jam lead singer who stopped mattering a really long time ago. This was an error, and it was contrary to AT&T policy, according to this August 2007 story. Yet the example is one of a few used to argue for net neutrality regulations.
Do we really want the government treading any of this ground?
Most people would probably agree that web site operators should be free to publish or not publish whatever they want. Regulations barring web sites from editing out controversial political statements, or requiring them to broadcast them, would be facially unconstitutional. Strangely, proponents of net neutrality regulation tout this kind of regulation as a virtue at the Internet's transport layer.