I bet couch is right on the year estimation.
As CDPR is not Bethesda to release an unpolished game with 500+ bugs and then milk the mokey with expensive DLC in a buggy game without fixing those bugs.

CDPR respects all audience which includes nitpicks like me, plus their DLC is free. Since there is no reason to believe they'll release a half-done project, 2016-2017 is my guess too.