Seeing as studios aren't even using the seven offered by the new formats (all of the HD-DVD and Blu-ray releases to date have been 5.1), I doubt we'll see any widescale use of 13.1 anytime soon. It's more a matter of including the infrastructure because they can.

As for the DVD-A/SACD war, I'd question that either side won. New DVD-A releases have ceased, and while there are still some new SACD titles appearing they are almost entirely from smaller labels like Telarc - even Sony has pretty much left SACD for dead.