One big thing is that not many models of Windows Phone are currently even available in the US. I just visited the websites of VZW, Sprint, AT&T, and T-Mobile.
VZW only has one Windows Phone, the HTC Trophy.
Sprint only has two Windows Phones, the HTC Arrive and the Motorola ES400S. The Motorola device is $549 with a 2-yr contract.
AT&T has two Samsung models and one HTC model.
T-Mobile has the Nokia Lumia 710 and the HTC Radar.
All of the four major US carriers have more models of Blackberry devices at this time.
I expect to see Windows Phone to sell more once the carriers have more models available.
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