While NIS America never committed to a solid PC release date for the psychological thriller Psycho-Pass: Mandatory Happiness, it only took a few days of the console release to see the Steam version officially pushed away from its vague '2016' release.
Reaching out to NIS America themselves, they simply had this to say on the matter "When we first announced the game, we announced it would be available on PS4, Vita, and Steam - but in April 2016 we clarified that the game would release on 16 September for PS4/Vita, and would let everybody know the Steam versions' release date later on. Now in September, we finally reveal that the Steam version of the game will be available in 2017".
Steam users are adamant the Store page once listed a 2016 date, whereas NIS America seem to be reluctant to give a reason for the possibly staggered release of the PC version. It's entirely possible the PC version just needs a little more time in the oven to run properly on the wide variety of PCs out there - or maybe they're simply looking to increase marketing efforts a little more. Either way, the release date is still just as vague as before - now it's just even further away.
Might as well add it to your Steam wishlist now. At least you'll get email updates.