The Diamondbacks would like to move one of their outfielders before Spring Training, if not this week (which has been a rumored, though apparently not a firm, deadline). The Snakes will either trade Justin Upton or Jason Kubel. With Upton, apparently the only suitor left standing are the Atlanta Braves. The biggest obstacle therefore to a JUp trade going down with Atlanta seems to be if the D-Backs decide to trade Jason Kubel instead.
The news on the Kubel trade front is that apparently not many folks are interested.
The Orioles have been the only team "rumored" to be interested in Kubel, but that doesn't mean other teams aren't out there lurking. Kubel has a much lower price tag, so the barrier to entry into that trade sweepstakes is much less than the Upton sweepstakes.
What all this means is that in assessing the Braves ability to double-UP (there will be more puns), we also have to keep an eye on the Kubel trade rumors.