DH will be back stateside next week (yay!)
I'm so sorry you are even facing this dilemma. That really, really stinks.
I am spending Christmas apart from DH this year. It isn't exactly what I want but we made certain plans and now feel we have to stick to them.
However, we don't have a brand new baby! This is just my opinion but if it is an option for you to be with him for Christmas, I would do it. I know how important my family is to me but if it was between being with my family (parents and brothers) or having a first Christmas as a new little family, I would try to do that.
Is there a way you could just fly out for a few days so you don't have to try to do the big move on such short notice? Or, since Christmas is on a weekend, could he try to get a 4 day pass and fly to be with you? It would be worth a shot for him to at least try that. They may be willing to work with him more since it is Christmas.
Good luck. I understand how difficult it is wanting to be in two places at once!