So far it is... I've heard rumors of firmware updates sneaking out to a few people early, but those are just rumors.
EDIT:
Updated with source information on dates:
DTS today announced DTS:X will be activating its first two AVR brands via firmware updates, including Denon’s AVR-X7200W (January 28), the AVR-X6200W, and the AVR-X4200W receivers (February 18). In addtion, Marantz’ AV8802A pre-amplifier on (February 4), Marantz SR7010 and SR6010 AVRs (March 3), and the Marantz AV7702mkII pre-amplifier (March 3) will all activate DTS:X this year.
The only ones getting anything above a 7.1.2 or 5.1.4 setup are the two pre-amps which are able to do 7.1.4, or *possibly* 9.1.2 (still not seeing anything more about wides being or not being supported with the first run of DTS:X. That news came from a Trinnov rep at CES, and since they are pretty high end, it is interesting that they are saying that wides aren't supported since they have pretty capable hardware).
