Nikon is expected to release a new J2 camera (replacement for the Nikon 1 J1) and some new mirrorless accessories, including an underwater housing. The announcement should happen around mid-August. Do not expect any major changes in the spec and design of the J2. At that point I am not sure if there will be also a new V2 mirrorless camera to replace the current V1 model.
Nikon is also rumored to announce a new slimmer standard zoom for Nikon 1 mirrorless cameras - probably the lens on the left (image: Nikon 1 lens concepts on display at the 2011 PDN PhotoPlus show in New York):
I already mention that Nikon will have multiple announcements in the weeks before Photokina. There is more to come, stay tuned.