One of the things in the way of this concept are the huge LCD's on the back of cameras these days. If you want a 3.5 inch wide screen LCD on the back of an SLR, it won't be a small camera.
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How do you figure?
Check out the Sony DSC-TX7 sometime. It's got a 3.5" (diagonal) touchscreen and it is 3.9x2.3x0.87". The Iphone has a 3.5" touchscreen too, and it is even thinner, but a bit longer than the Sony camera. A screen doesn't add much to the device other than a frame to hold it in.


