GigaOm published two interesting articles by Joe Weinman: in the first one, he describes why pay-per-use residential broadband Internet is probably inevitable, in the second one he predicts changes in user behavior if the service providers decide to implement it. I would also suggest you take time and read his in-depth Market for Melons article.
Obviously, collecting money costs money and the pay-per-use model is no exception (not to mention that most people would pay less), so the service providers prefer usage caps. There are numerous ways to implement usage caps, but implementing usage cap as an acceptable use policy and calling exceeding the cap policy violation is not the way to do it. Some people are truly trying to alienate the users.
Last but definitely not least, the Comcast/L3 saga continues, with leaks documenting saturated upstream links and Level3 trying to apply all sorts of legal pressures on Comcast. Enjoy the show!
I’ve been describing the challenges of broadband residential Internet in Market Trends in Service Provider Networks webinar (buy a recording) and Upcoming Internet Challenges presentation (recording available as part of yearly subscription).