Nikonrumors.com spotted a note on NikonUSA's webpage on its WU-1a wireless adapter that states that the Nikon D600 can use a "WU-1b Mobile Adapter." AFAIK, this is the first time any official Nikon page has mentioned the D600.
As for the wireless adapter, I'm not sure if that's a typo or if the D600 will use a WU-1b instead of a WU-1a. The WU-1a is a wireless adapter for the D3200 that allows sharing of images via WiFi and allows your smartphone to function as a remote live view device.
The page also mentions that the iPhone version of the software for connecting to the WU-1a will be available on September 15, 2012 (until now, it has been available only for Android).