In general, I would agree but it seems like the broadband provider space is a bit different. Those of us in larger metropolitan areas can freely switch between several providers but customers in more rural areas have very few providers to choose from (if any). Many of the companies that DO serve up broadband in these areas enjoy a kind of local-monopoly. They can do pretty much anything they want because there are no other competitors around. Consumers in these areas are pretty much screwed if their provider decides to cap.
I think the market will adjust though. If enough people get bad enough service, someone will come in and give a better service.
Assuming there aren't regulatory or other barriers to entry.
The US does seem pretty bad where these things are concerned though.
In the UK we have literally hundreds of broadband suppliers to choose from. Yes the majority go through BT, but the terms etc are decided by the broadband suppliers, so you have loads of plans to choose from - capped, uncapped, cheap, expensive, etc etc
We've had capping since the introduction of ADSL in South Africa.
To give you an indication as of today I've used 4362MB of my 5GB cap. For which I pay $30 on top of my 512kbit/s line rental of $25). Yes, Internet sucks in South Africa.
We've got a population of +- 48 million, of which 4 million people use Internet and 1 million are using "broadband."
The high cost, low speeds, and small bandwidth allocations have hurt the growth of Internet here dramatically.
Will it strangle Web growth? No. Video and other multimedia? Yes. I think this decision on the part of providers like TWC has more to do with getting in bed with the MPAA and the RIAA than it does about costs or high-bandwidth users.
If one or only a few companies impose caps, look for rising market share of those companies that don't, probably about 1-2 billing cycles after the other companies cap downloads.
