It looks like the August 28th announcement is mainly a NEX event. The A mount lenses and the A99 could be announced two weeks later in mid September. Here is a wrap up of all info we have from our trusted sources. This is what Sony will announce:
NEX-5R: Looks almost exactly like the NEX-5n and has the flip screen from the NEX-F3. It has a completely newly designed 16 Megapixel APS-C sensor with Phase Detection AF pixels. It has WiFi connectivity and APP support. You can surf on Internet with it. Price around $700 with kit lens.
NEX-6: It’s a mini NEX-7 with integrated viewfinder. Compared to the NEX’7 it has an EVF with less resolution and a newly designed 16 Megapixel APS-C sensor (with Phase AF pixels?). It has WiFi connectivity. Price between the NEX-5R and NEX-7 (NEX-7 is currently priced at $1200 at Amazon so my guess is around $950 and $1000).
Sony 16-50mm f/3.5-5.6: It is a pancake zoom. One “external” source (means not from SAR) says this is actually a non pancake f/2.8 constant aperture zoom.
Sony 11-18 f/4.0: UPDATE: It is not a pancake zoom!
Sony 35mm f/1.8: Fast non expensive prime lens as big as the Sigma 30mm lens.