Yup! You can go see the story
here at Anime News Network. Basically, vol 14 of xxxholic will come with an OVA DVD, when it comes out 1/16/09. It's part 1 of a 2-DVD OVA. All the seiyuus seem to be returning for it, and it is being done by the director of the Tsubasa OVA and the director of all the xxxholic anime produced so far.
So, what do you think? Will it be like the Tsubasa OVA and stay truer to the manga? Will they include more of the Tsubasa parts of the OVA with this?