I don't see Outlaw releasing a SW update to the 975 incorporating DTS-X. I would imagine there's some significant development cost, assuming it would even fit within the fixed memory size of the 975. I don't see Outlaw giving that SW away and I don't think they've ever had a SW upgrade for purchase, although it's an interesting idea.

For the new processor, from the little I read, the hardware should be the same for Atmos and DTS-X so it's "just" software. I would expect to see both formats implemented, especially given recent announcements.