With the recent redesign of the whole close system, there seems to have been an inadvertent corollary.
Namely, in the "Reopen Votes" review queue, when one clicks "Leave Closed", there is a popup saying "Nominate this question for reopening?"
Clicking Cancel records a "Leave Closed" review (thanks Asaf for digging that up). I haven't tried what OK does.
As the observant have undoubtedly inferred, I use Chrome (latest) and Windows (7).