I've never been a fan of the Four Thirds format. When it first was introduced I complained on these pages that it was a step in the wrong direction. We needed larger sensors, not smaller ones.

Theraison d'etrefor 4/3 was to make cameras smaller, and though the first models were somewhat smaller than their 1.5X and 1.6X competitors, it wasn't long before Canon, Nikon and others started producing DSLRs that challenged what Olympus (primarily) was trying to do with the new format.

The problem was that once you have a prism and a mirror assembly there is a lower limit to the size that one can make a camera, even with a 2X (1/4 area) sized sensor. This challenge lead within the past year to a new generation of Four Third format cameras –Micro Four Thirds.

With M4/3 it isn't the sensor that's been reduced in size, its the cameras themselves. This has been done by dispensing with the whole mirror / prism mechanism, relying instead on just the rear LCD and Live View, or in...