The new Nikkor Z 70-180mm f/2.8 lens is already shipping from B&H Photo and is already in stock in Canada and UK:
Check Matt Granger’s sample files from the Nikkor Z 70-180mm and 70-200mm f/2.8 lenses:
See also the lens review posted on the Nikon Z Mirrorless Cameras Facebook group.
Previous coverage of the Nikkor Z 70-180mm f/2.8 lens is available here:
Nikkor Z 70-180mm f/2.8 vs. Nikkor Z 70-200mm f/2.8 VR S specifications comparison
Nikkor Z 70-180mm f/2.8 and 180-600mm f/5.6-6.3 VR lenses additional coverage