T-Mobile reported yesterday that the company, due to "overwhelming demand," had pre-sold all the G1s it had initially ordered from handset maker HTC. Perceived as the first worthy competitor to the iPhone, the suggestion is that it could sell half a million units by the end of the year. The phone officially goes on sale October 22. 

I was in Google's NY offices today and tried to get my hands on one to no avail.

Meanwhile, several sources are reporting the unverified estimate that Apple may have sold its 10 millionth iPhone. (However, it may be more accurately that 10 have been produced.) Separately, CNET cites NPD Group figures that claim 30% of US smartphone buyers switched to AT&T to get the iPhone.

Here's where NPD says the defectors came from (6/08-8/08):

• Verizon 47%
• T-Mobile 24%
• Sprint 19%

Given this, the G1 emerges as a defensive strategy against the iPhone as much as it is a bid for new customers. Still it may attract some new customers to T-Mobile until other carriers begin to offer their own Android-based phones (probably at least six months away).  

What these data above reflect is the growing demand for better mobile user experiences.