I can't speak to companies with high inertia like AT&T or Sprint, but small associations, like those in the midwest, are already providing fiber optic all the way to the handset for landline based home customers; and these sets are digital, although not IP phones yet.
Because practically all these organizations are also the sole provider of ISP services, they already have enough infrastructure to convert to total IP based digital services. And at very affordable rates. Most are simply waiting for the cost of final loop optical networking hardware to drop in price. When this occurs the conversion will be rapid and overhead minimal.
The analog handset is as good as dead!
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