Total BS. As the operator of an ISP (and a former columnist for InfoWorld who was dismissed because I didn't go along with Microsoft's monopoly propaganda... not much different from monopolist Google's fearmongering above), I can say with authority that no ISP wants to limit what sites users can visit. That's the scare tactics that the lobbyists are using to push so-called "network neutrality" regulations, which are not neutral at all; they're designed to tip the economic balance away from ISPs and toward content companies such as Google. The regulations prohibit ISPs from charging more when content providers waste bandwidth or attempt to demand priority delivery of their content -- in short, when they ask for something for nothing. They also prevent ISPs from blocking software that exploits the ISP's network for the benefit of a content provider. In short, they're all about regulating the Internet in ways that benefit powerful corporations. Worse still, they let the camel's nose into the tent. If the FCC can regulate the Net to advantage Google, it can also regulate it in other harmful ways. Want to see censorship? Government blocking of sites? Even more intense spying on your Internet activities? If these regulations are not overturned, the precedent will open the door to all of those things.
There's too much competition. I live in a small, rural town of 28,000 souls, and we have 12 (count them!) facilities-based ISPs and more non-facilities-based ones. ISPs know that if they do anything that riles customers, those customers are history.
On the other hand, every government that's gotten control of the Internet in its country has censored it. Without exception.