The Nikon ZF.2 version is not yet shipping; however, it is available for pre-order.
Carl Zeiss will be showing off the new Apo Sonnar T* 2/135 lens at Photokina 2012. The new lens will be available for Canon and Nikon mounts in the ZE and ZF.2 series, respectively.[youtube http://www.youtube.com/watch?v=qFMhilBU7BU&w=640&h=360]
The new Zeiss lens should be available in December 2012 for around $2000.