The date was referenced in the company's Comic-Con line-up, though no specifics were mentioned. We suspect that the release window is subject to change.
The company confirmed a December release date for the Japanese version of the game earlier in the year. At the time it merely said that Final Fantasy XIII-2 would release "early 2012" in the West.
January sounds soon, but if Square Enix has fixed the issues we had with the original Final Fantasy XIII, we'll be more than happy to dive into the melodramatic series once again.