Yesterday, Fannie Mae announced a $17 billion profit for 2012, a complete turnaround from its near $17 billion loss in 2011. Where did Fannie's newfound profitability come from, and what does it mean for the housing and mortgage markets?

In the following video, Motley Fool financial analysts Matt Koppenheffer and David Hanson tell investors what this complete change of direction means to them, and what they may be buying because of it.