Aaron gets some hands-on time with the Nokia Lumia 900, one of the many devices announced today at CES 2012 in Las Vegas.  The Lumia 900 will be exclusively available on AT&T later in the year, and marks Nokia's re-entry into the US smartphone market (on the high-end, at least).  Specifications include a 1.4 GHz single-core processor, 4.3-inch AMOLED display with Nokia's ClearBlack technology, an 8-megapixel camera with 720p HD video recording, a front-facing camera, 4G LTE connectivity, and Windows Phone 7.5 (Mango).  It's a stunning device, but it'll go up against the HTC Titan II, the first phone with a 16-megapixel camera to land in the US.  Will it stand up against the competition?