Not that either company cares what I think, but I'll just say again I think it's very shortsighted (if not downright foolish) of Olympus and Panasonic not to have designated a preemptive official abbreviation for "Micro Four Thirds" right from the get-go. After having read our readers' many thoughtful suggestions, I'm going to go with "m4/3" on this site.
As regular readers might remember, I tried to establish "mm-e" among various photography webmasters as a common abbreviation for "35mm equivalent." I got several long replies explaining why 35mm-equivalent focal lengths was not a valid concept and why they weren't going to go along, in several cases from individuals who then went right ahead using the concept on their websites, but continuing to write it out in long, ponderous English.
Years before that, I tried to peg "digital photography" as the ugly bastard term it is, and to suggest that "photography" should be reserved for traditional optical/chemical photography (with its "straight" products being called photographs) and that digital-electronic methods should be called "digital imaging" (and its products "digital images"). Anyone who reads about photography today knows how far that duck flew. So I've given up trying to influence the standardizing of photographic terminology. I'll write "Micro Four Thirds" as "m4/3" at least until the rough consensus of conventional usage overrules me, at which point I'll switch over and do whatever everybody else is doing.