I thought that the Four Thirds system was (is) nice and think that the Micro Four Thirds system is great, but ironically one of the things that I have never been quite sure about is the 4:3 aspect ratio from which the two systems draw their names. I did and still do shoot Canon DSLRs which use a 3:2 ratio and so the wider format feels natural to me. A 3:2 image draws your eyes from left to right and back again (or up and down in potrait). In comparison a squarer image feels more static. This does not necessarily make 3:2 better, just...different. One of the coolest things about my GH1 is the multi-aspect sensor which allows me to shoot at 3:2 using the full image circle, with the loss of only about 0.5MP compared to using 4:3. It also helps to make full use of the ultra-wide lenses like the 9-18mm. Of course you can always crop a 4:3 image, but you don't get quite the same width. I wonder how much extra cost is involved in the multi-aspect sensor that would prevent it from being used in a wider range of models, and does the system name preclude a dedicated 3:2 sensor ever seeing the light of day?