|The Olympus E-5: Never a good camera.|
One super-cool feature that is practically tailor-made for the 4/3 format is the 1:1 sensor. Most sensors are either 4:3 or 3:2. The 1:1 ratio is beloved by large-format and medium format photogs because it eliminates many framing considerations. You never have to hold the camera sideways. And specifically of interest to 4/3 is that it would allow them to increase the surface area of the sensor, netting image gains, without having to redesign any elements of the lenses and standard. Everything would still work.
Any format could do this, but with most full-format cameras, the camera body is already as small as possible around the sensor. The 4/3 sensor is small enough to allow a 1:1 ratio with no impact on body design.
The fact that Olympus is likely not bringing something like this to the game is very, very disappointing. I hope that this is not Olympus being Olympus... again. The release of the world-class 75mm and the E-M5 elicited hope from many long-suffering Micro 4/3 users. I hope that we don't need to start suffering again.