Today I've remembered about this vapourware. It seem that they've actually made their comparison public in october:
http://aws.otoy.com/docs/ORBX2_Whitepaper.pdf
It says that they have been comparing against x264 --preset slow --bframes 0 --tune ssim / --tune psnr (which is quite sane).
I've been trying to reproduce it and, well, obviously SSIM values are wildly different (--crf 18 gives SSIM-Y 0.9903910 = 20.173 db @ 6289.24 kb/s), so either there're different ways to calculate SSIM in db, or dunno. For PSNR they've used "PSNR-HVS-Y" and I have no idea how to do it.
UPD: oh wait, they do have normal PSNR-Y graph. Real x264 results are:
43.207 @ 2016 kb/s
45.057 @ 2968 kb/s
46.303 @ 3990 kb/s
47.102 @ 5036 kb/s
49.347 @ 10068 kb/s
It might be not that accurate (who knows how they've preformed RGB->YV12 conversion), but still it's much higher than numbers they got and beats their numbers (which could be fake as well).