The unveiling is expected to occur at an event that is scheduled on the 24th of August. According to the rumors, new lenses are expected to be unveiled along with the three brand new cameras, and they are the Carl Zeiss 24mm f/1.8 fixed-length lens, a 55-210mm f/4-6.3 super zoom lens and a 50mm f/1.8 OSS (Optical Steady Shot) lens.
As far as the camera specifications are concerned, the NEX-7 is expected to target the more professional users who may require a smaller sized camera. It is also expected to be a rival for the Fujifilm X100. The Sony NEX-5N is said to be a refresh of the NEX-5 with a new sensor and a build that is somewhat similar to the NEX-C3. Unfortunately not much is known about the Alpha A77.