
Phone company plans always used to be pay-as-you-go. The development of unlimited use plans arose as a marketing tool to win more customers in competitive markets, and it eventually became a very common option in the consumer market (businesses almost always have pay-as-you-go plans). If this really happens, it won't take a rocket scientist to realize that any ISPs who stick to no-cap unlimited use plans will immediately have a competitive advantage over others (like [...ahem..] Comcast) who are likely to try to milk the new cash cow afforded by such changes.
The problem here is that the majority of ISP's have NO competition in a given area. It's difficult to compare Cellphone providers to internet ISP's such as Comcast and TimeWarner. Cellphone companies fight for your business because you have a somewhat decent choice of who to go with. Verizon, AT&T, T-Mobile, Sprint etc. In my area, Comcast has no competition. I can't get anything else, so why would they want to offer a fair deal, when they know they have customers by the balls. The ISP monopolies is one of the real issues here.
"If people are good only because they fear punishment, and hope for reward, then we are a sorry lot indeed." -- Albert Einstein