There are several possible business models: Charge every customer the same amount, charge per Mbps, charge per GB, etc. I don't think there's one "obviously correct" business model.
it's not to say that there is one obviously correct model, but to say there are clearly very incorrect models.
While portions of the public want to buy 'unlimited' service, the only way that 'unlimited' service can exist at rates not deemed unrealistic is if most users of the 'unlimited' services do not create heavy usage. It's a tanstafl issue; once everyone is a heavy user, the subsidy created by uneven usage no longer exists.
