Well everyone thought it was going to go live in the last update but everyone got a surprise when it turned out to be coldfront instead.
I heard it had something to do with Psy not getting it ready for Valve in time for certain schedules but you'll have to wait for a reply from him, obviously, to confirm details. This is one of the community maps that really deserves to go official, not only are the aesthetics stunning but the gameplay actually works. Something you (unfortunately) can't say for many of the other community maps...