Microsoft's Windows Phone 7 operating system is expected to bring a series of jaw-dropping handsets to the market, and one of them just leaked into the wild, the Dell Lightning. Running under the newly unveiled mobile client from Microsoft, the device is reportedly heading to the market in a portrait sliding form factor, with a QWERTY keyboard on board, and with more than appealing looks.

The photos of Dell Lightning, brought to the web by Engadget, show a sleek device, which seems to include highly appealing specs too. Among them, we can count a 1GHz QSD8250 Snapdragon processor, a 4.1-inch OLED capacitive touchscreen display that boasts a WVGA resolution, 1GB of internal memory, 512MB of RAM, and 8GB of storage on a MicroSD memory card, which might not be user-replaceable.

Other specifications of the device include a 5-megapixel photo snapper, built-in GPS receiver, accelerometer, FM radio, 3G connectivity options (with support for HSDPA 7.2Mbps), full Flash support, Wi-Fi, Bluetooth 2.1 and USB 2.0 (microUSB) port, compass, proximity sensor, ambient light sensor, music and video players, and more. The upcoming Windows Phone 7 device is powered by a 1400 mAh battery, while measuring 64.4 x 121.6 x 14.9 mm.

According to Engadget, the new mobile phone is expected to receive an upgrade to LTE sometime in the fourth quarter of 2011, which sounds quite interesting. As for the release date of this Windows Phone 7 device, Q4 2010 is the lucky time frame, in line with the expected availability of other similar mobile phones. Unfortunately, some appealing features in the above list will not be present at launch, such as Adobe's Flash Player, but they should be added into the mix soon after.

Leaks always provide a reason to rejoice to enthusiasts, but it still remains to be seen when the official confirmation on this handset's launch will arrive. Hopefully, it won't be too long, so stay tuned for more details on the matter. More leaked info and photos can be found over at Engadget here.