Last night, we got a tip telling us that this morning, Barnes and Noble's ship date for pre-orders of the Nook would slip further -- from the previously known date of January 11th to January 15th. And hey, what do you know? The BN website is now showing an expected ship date of January 15th! Disappointing for all of us who are expectantly awaiting our units, no doubt, but there's the possibility of further bad news. The last time we checked in, the Nook was expected in some Barnes and Noble retail stores on the 7th of December. This tipster, who as we've just mentioned proved spot on with the pre-order date (and whose name we k