The Lumia 900 carries the hopes and dreams of two companies on its shoulders: Nokia, which is looking to re-establish itself in the U.S., and Microsoft, whose slick Windows Phone software has yet to catch fire with consumers. No pressure, right? The $99 Lumia 900 for AT&T looks like it has what it takes to light the way, offering 4G LTE speeds, a premium design and an 8MP Carl Zeiss camera. Nokia also throws in its own apps and content unique to its flagship. Is all of that enough to finally put Windows Phone on the map?