While I find m4/3 small size nice for some things (parties, bycicle tours, casual stuff) I find a nice OVF and more important a certain size and weight of a camera body just the better tool. More stable in the hands, buttons better to reach without looking at it, better viewfinder, faster lenses.
Maybe I am old fashioned but m4/3 still does feel to small with too many buttons and video-camera-like viewfinder for me as an overall camera. Even without owning one a E5 is - IMO - much more camera than a GH2 or G3 or EP3.
size, amount of mp and high ISO noise are the most overrated features IMO today.