I know some cameras or at least video cameras have bluetooth, or now even WIFI, but I don't know of any that communicate with each other. Not sure of the goal of them communicating with each other?
On the other I believe that at least some of the two way radios that have built in GPS recieves exchange the GPS data with each other. This sounds very cool and usefull. Each person in the field will know where the others are.
As far as storing the GPS data as an EXIF field, if a camera stores it then most programs should support viewing the data. I believe it is a standard EXIF field.