There’s no source quoted for the dates but Siliconera are talking about some upcoming DLC for Drake’s latest adventure. According to the site with the gaming dinoaurs the content will kick off with a free pack launching at the same time as the demo (January 28th). This first pack will contain multiplayer skins of characters from other famous PlayStation brands, Resistance 2, inFamous and Killzone 2.
There will be a further two packs on February 25th and April 15th which will introduce new maps and skins, including some content from the original Uncharted.
Thanks for the tip, haz360!