The Doctor Who 2014 Christmas Special, is now available to pre-order on DVD and bluray. Last Christmas is released on Jan 26, 2015 and also features the accompanying episode of Doctor Who Extra. Orders from the BBC Shop also come with an EXCLUSIVE art card. Buy on DVD HERE and on Bluray HERE.
UPDATE: Also included is an audio commentary with director Paul Wilmshurst and producer Paul Frift.
For more info on Last Christmas, visit the guide to the Christmas Special HERE
AmazonUK have an image of the back cover on their product page which lists a commentary as a special feature. Any details on this?