Recent article in leading PC magazine "c't":
No DTS:X hard/software or information at IFA show.
DTS:X firmware upgrades for amplifiers have been "postponed indefinitely", at least until early 2016. There seem to be serious issues with the programming of the algorithms for the common DSP platforms from AD, TI and Cirrus. Also, the hardware manufacturers did not get any decent documentation of the DTS:X format.
Earlier this year, DTS:X tried to compete for the audio part of the upcoming ATSC 3.0 specification, but had to back out shortly after, due to lack of documentation and explanation.
"Ex Machina" is the only BluRay with DTS:X, and "American Ultra" has been announced in DTS:X; "Sicario" and "Mockingjay Pt. 2" are supposed to be released theatrically in DTS:X, so their BluRay releases might feature DTS:X as well. However, no further movies have been announced in this format.
My conclusion: DTS is on a bumpy road, due to its very late decision to join the race. On the other hand, we now have 4 rather similar 3D Audio formats: Dolby Atmos, DTS:X, AuroMax, and MPEG-H. All of them combine conventional audio channels, including 5.1, with object audio and some additional functions. That might help to convince professionals and studios to produce more 3D audio content, since chances are good that it will be compatible with theatrical and home speaker setups, and maybe it will even be possible to convert between these 4 formats, or at least derive all 4 from a generic master mix. Also, prevalence in theatres and homes might improve due to these reasons, in turn stimulating content producers even more. Hope for the best!