As rumored, Nokia announced it third real Windows Phone, Nokia Lumia 900 a.k.a. Nokia Ace. Sadly, it is exclusive to North America which will come with AT & T. It is the first Nokia phone to feature LTE connectivity which will take full advantage of high speed network of AT & T ‘s 4G network.
Nokia Lumia 900 has 4.3″ AMOLED ClearBlack Display having resolution of 480×800 px and with Cornering Gorilla Glass. It also features 1.4 GHz CPU, F/2.2 8 MP wide angle Carl Zeiss Lens Camera, 1830mAh , etc. The missing thing in Lumia 800, a front facing camera, is also added in Lumia 800 which is 1 MP camera supporting Video Calling.
Watch Nokia Press Conference at CES 2012 announcing Lumia 900:
Also have a look at First Hand on Lumia 900 from Nokia Conversation,
It is not yet announced if Lumia 900 will be available outside later on or not. They also didn’t mention when it will become available in US.
Head to Nokia’s official site for more specifications and details: http://www.nokia.com/us-en/products/phone/lumia900/