Microsoft showed off the prototype for its first Windows Phone 7 Series device, manufactured by LG and featuring a sliding physical keyboard, at The Engadget Show on Feb. 27. The phone apparently includes a 5-megapixel camera with flash, a headphone jack and the requisite three mechanical buttons (Search, Home and Back). This image of the device, which was unveiled by Aaron Woodman, Microsoft's director of Mobile Communications Business for its Consumer Experiences Product Management team, comes from Engadget:

My first thought: Droid. But whereas the Motorola Droid was built to be the telecommunications equivalent of a brick, this LG device seems smaller and sleeker. The choice of form factor seems tailor-made to appeal to the broadest possible smartphone-user demographic, by servicing those who (like me) hate typing on a virtual keyboard.

However, this is just a first look. The user-friendliness of hardware is something determinable only by testing said hardware for yourself, and neither Microsoft nor its OEMs have offered a hint of how Windows Phone 7 Series will interact with its mechanical elements; as I pointed out in my November review of the HTC Droid Eris, it's the little details--such as that device's reliance on a difficult-to-use trackerball to operate the camera--that potentially make or break a phone.

Windows Phone 7 Series' early adoption will also be determined, to a certain extent, by the durability of the first operating-system version: If it's buggy and Microsoft doesn't push through updates on an expedited basis, then potential users could shy away. If it's stable and fulfills the promise suggested in videos during the Feb. 15 unveiling in Barcelona, then the device could come strongly out of the gate, provided it's paired with good hardware. Early sales of the Motorola Droid were strong precisely because the Verizon-led ad campaign managed to sell the device as an ideal synthesis of software and hardware, while Apple has grown its market share by marketing the iPhone as an epitome of industrial design that offers an app for anything.

I have no doubt that Redmond and its partners are studying every aspect of those campaigns to best figure out how to market Windows Phone 7 Series. But now that LG has provided a preview of its device, I'm wondering about the other ones in the lineup: Microsoft evangelists have hinted that there will be three types of form factor:

1.) The version with the sliding physical keyboard (like LG)

2.) The version with a full touch screen and no physical keyboard (reminiscent of the HTC Droid Eris)

3.) Hinted to be a candy-bar form factor (perhaps like the Palm Pixi)

Microsoft's challenge now will be to help shape an ecosystem whose devices work well with its software. The LG device suggests they could be off to a solid start, but more details need to be forthcoming.