Well, they did say they'd house the a65. Same OLED electronic viewfinder, same sensor, same just about everything aside from AF points and max shutter speed (but max flash sync is probably the same). Slightly slower burst rate. I think the a65 even has the same option of electronic first-curtain shutter. Just smaller bodied, more standard controls (no joystick), and without lens focus calibration.
I could easily see upgrading to an a65 for underwater and having an a77 body for above. My primary interest in the a77 is body ergonomics for out-of-water use, the better rear screen actuation, and focus calibration for tele use. None of those three topics really apply below the surface.
Edited by rtrski, 06 December 2011 - 08:30 AM.
Current rig: Sony SLT-alpha55 in Ikelite housing, Sigma 105mm f2.8 DC Macro w/ Ike 5505.58 flat port or Sigma 8-16mm f/4.5-5.6 DC HSM behind UWCamStuff custom 5" mini-dome. Dual INON z240 Type IVs triggered with DS51 for TTL mimicry, or DS51 alone with home-made ringflash assy for macro.
Topside, unhoused: Sony SLT-alpha99, Sigma 150-500mm + 1.4TC, Sigma 15mm diagonal fish, Sony 24-70mm f2.8 CZ, Tamron 180mm f2.8 Macro...all the gear and nary a clue...