Nov 8, 2010 14:01 GMT  ·  By

The first smartphones running under Windows Phone 7, the new mobile operating system Redmond-based Microsoft brought to the market a few weeks ago, are now available for purchase on shelves in the United States.

Starting today, US users can purchase three such devices, namely the HTC HD7, HTC Surround and Samsung Focus, with some more expected to arrive soon.

The new Windows Phone 7 OS comes with a nice range of enhancements and improvements when compared to the older Windows Mobile platform.

The new OS iteration marks a new beginning for Microsoft on the smartphone market, while better positioning the company on its fight against rival solutions, such as Google's Android OS, or Apple's iPhone.

Backed by a nice range of appealing services, the Windows Phone 7 OS seems pretty appealing, though it does not benefit from a large application ecosystem for the time being.

Even so, the handsets it powers are all high-end, and they already managed to impress users in European countries, previous reports suggested.

The aforementioned US-bound Windows Phone 7 smartphones were made available for purchase via two wireless carriers in the country, namely AT&T and T-Mobile each of them priced at $199.99 on contract.

Those of you interested in the purchase of any of these three devices will find them available via Microsoft's online Store too, here.

Of course, the smartphones were made available for purchase via the respective wireless carriers too, as well as via various other retailers around the United States.

The HTC HD7 is the first Windows Phone 7-based device at T-Mobile, and should be followed by the Dell Venue Pro in the coming weeks.

While making the HTC Surround and Samsung Focus available on its airwaves today, AT&T plans the launch of another Windows Phone 7 handset in the near future, the LG Quantum.

Next year, we should see even more Windows Phone 7 devices brought to the market, as well as more features added to the platform itself.