LG Quantum Windows Phone: US$199.99 @ AT&T

AT&TEngadget: The LG Quantum Windows Phone 7 smartphone is now officially available on AT&T for $199.99 with a new two-year agreement. The Quantum sports a 3.5-inch, 1GHz CPU, 16GB internal storage, a 5 megapixel camera, and a slide-out QWERTY keyboard.

Here are some reviews. ZDNet:

Typing on this keypad is much easier than others given the large frame of the phone to start with. […] The only commonly-overheard complaints with the Quantum’s keypad was the odd Shift key and the lower placement of the Delete key (where you’d normally find the Return button, which is now a bit lower than usual too).

Wired:

Some apps move from portrait to landscape without a hitch. But the WP7 home screen, Marketplace and a few others don’t. In time, you could get over this guessing game. […] The keyboard also made the phone quite thick, particularly compared to the touchscreen-only models on display.

SlashGear:

But, while the outside of the device may not be all that great, and it certainly features the smallest display of all the devices launched, the keyboard is amazing. The keys offer great feedback, and they are tactile in such a great way that we’re confident this could be one of the best hardware keyboards out there.