This drawing of T-Mobile's Lumia 710 appeared on the FCC website

T-Mobile and Nokia have tried to maintain a veil of secrecy around their upcoming announcement, set for Dec. 14 in New York City. A joint invitation sent to media suggested "something exciting in the works" but was otherwise bereft of detail.

Nonetheless, given how Nokia is solely in the Windows Phone business, it wouldn't have taken Sherlock Holmes to deduce that some sort of Windows Phone device was in the unveiling.

The bigger question was whether T-Mobile and Nokia would unveil the Lumia 710 or 800, or a new device altogether. The Lumia 710 is priced as more of a midmarket phone, while the Lumia 800 targets the higher end of the price range.

Nokia's Lumia 800 (left) and Lumia 710 (right)

Pictured at right above, the 710 has a 3.7-inch touchscreen with a resolution of 800 x 480 pixels, a five megapixel camera, and a 1.4GHz, single-core Qualcomm MSM8255 processor. According to Nokia's October announcement of the device in Europe, it offers 512MB of RAM and 8GB of flash storage, but no microSD expansion slot. (For further details, images, and a spec table, see our earlier coverage.)

Earlier this year, Nokia abandoned its homegrown operating systems, including Symbian, in favor of Windows Phone. Both the Lumia 710 and 800 run the latest "Mango" variant of Microsoft's smartphone platform. With that software in place, the Finnish phone-maker hopes to retain its global presence in the face of fierce competition from both Apples iPhone and Google Android devices.

But both Nokia and Windows Phone have an uphill battle for a substantial piece of the U.S. smartphone market. Microsoft owned 7.3 percent of the U.S. smartphone market in the third quarter, according to new data from Nielsen. That number includes both Windows Phone and the older, largely discontinued Windows Mobile. Moreover, that number trails Research In Motion's BlackBerry at 17.8 percent, Apples iPhone at 28.3 percent, and Google Android at 42.8 percent.

Earlier this year, the firm placed Microsoft's share of the market at 9 percent, trailing Android at 39 percent, Apples iPhone at 28 percent, and RIM's BlackBerry at 20 percent. Microsoft routinely refuses to release any hard data relating to smartphone sales, leaving it up to third parties like Nielsen to offer their own numbers -- and even then, the lingering presence of Windows Mobile clouds the ability to tally Windows Phone.

Nokia also has a small presence in U.S. smartphones, something it wants to change over the next few quarters. Despite what will surely be a significant marketing push, some analysts remain doubtful about Nokia's and Microsofts combined chances.

"With no breakthrough innovation, we believe Nokia's new phones are unlikely to get traction in a highly concentrated high end," James Faucette, an analyst at Pacific Crest Securities, wrote in a research note quoted by The New York Times Nov. 22. With that in mind, he set Nokia Windows Phone sales for the quarter to 500,000 units, down from his previous projection of two million.

However, Windows Phone has also attracted stronger developer and consumer interest, according to other surveys, which could bode well for the platforms future prospects.

Nicholas Kolakowski is a writer for eWEEK.

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