Imagine a model of a completely differentiated service arrangement. Open a TCP connection, pick a bandwidth, cost of connection will be more if bandwidth more. We mainly heard today about small transactions from many locations. So bandwidth of a single connection is not a predominant concern. We're hearing that ISPs want to offer a few, say five, grades of service.
Key thing is differential pricing.
Once you start charging extra, you must be able to prove that the customer is getting what they paid for. Service level agreements. We only get our money if we can prove that we did what you paid for. Your expectations are met. It's not clear how many levels of service the market really wants.