Where it is currently 2013 - I'm with Keith on "Best Work for 2012" as being the reason for an award or recognition. Realize that whenever you cite internal company awards, the details of the award is likely to mean almost nothing to most of the readers of your resume, as they won't know or care about the details of your company. Given that it is only January 2013 - one would hope that you haven't won a "Best Work" award for this year yet! And anyone reading the resume and seeing Best Work 2013 is likely to be a bit surprised.
One caveat - should you win an award known to the general public, then the rule should be go with the publicly known naming convention regardless of accuracy.
Also - in cases where you've won multiple awards, you'll probably default after a while to "recognized numerous times for outstanding performance" or something similar in the experience section - just enough to highlight that you're a go getter - which is the imporant part.
Congrats, by the way!