My experience is identical...I have an AT&T iPhone from work, but our personal cell service is with Verizon. In my experience AT&T doesn't have enough capacity in their network, resulting in severely overcrowded cells. At Newark airport, for example, you can get 5 bars but be unable to place call because the cell is maxed out.
But that is a New York Metro area problem. In many other parts of the country AT&T service is quite good. When I am at my client in Maryland I get 4 to 5 bars with AT&T and virtually no signal at all from Verizon. In Massachusetts I get good service from both.
I think the real issue with the idea of wireless broadband is not so much reliability of service as it will be cost and capacity. What kind of throughput will the customer get, and at what cost? Extending even wireless broadband into really rural areas is awfully expensive. They will either have to charge a lot more to rural customers than they charge urban ones, or else spread the cost out across all customers. Either way, I don't see how that lowers any prices.
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