The next Zenit M lenses will be the 50mm f/1.0 and 21mm f/2.8

DC.watch reports that Zenit will release two more M-mount lenses

Zenitar 50mm f/1 (a future lens, hinted at but without any mock-up or prototype being showcased)
Zenitar 21mm f/2.8, a prototype of which was showcased.

Thanks Mistral!