We just received a portion of AT&T’s 2012 roadmap from a trusted source, and it looks like AT&T isn’t playing around this year. There are some heavy hitters lined up for the first quarter of 2012, and one of the biggest smartphone launches of the quarter is currently scheduled to take place in mid-March. According to our source, the Nokia Lumia 900 is set to launch on March 18th, which has been rumored before. The phone hasn’t yet received technical acceptance however, so that date could change. The bigger news is the phone’s price: AT&T and Nokia are planning to launch this flagship smartphone at just $99.99 on a two-year contract. That price point would make this sleek smartphone an absolute game-changer for Windows Phone, and it makes sense when you think about how much money Nokia and Microsoft are planning to spend promoting the launch. We took a hands-on look at the Lumia 900 during CES earlier this month and Nokia could easily have a hit on its hands when this handset launches later this quarter.