I'm sure this will be a nice lens, and I do have a soft spot for the old fashioned great build and smooth manual focus feel of the Voigtlanders. However I'm still waiting and hoping for a true macro lens longer than the Oly 60mm, with more working distance to the subject, and with autofocus to take advantage of automatic focus bracketing/stacking. For me that would be a more flexible tool than a strictly manual focus prime. In that regard, the current Oly 60mm is more useful for me, but I do wish it had more rugged build and weatherproofing. So as they say with micro-4/3 "we are spoiled for lens choices" but there are still some gaps and opportunities for improving existing lenses.
For me, an Olympus Pro 150mm f/2.8 macro would be a more appealing new lens. The 150mm length is more than twice the length of the existing 60mm Oly macro lens and would have significantly more working distance. For macro work I would stop down to f/5.6 or more, but a maximum aperture of f/2.8 would be enough to still create pretty good subject isolation for general use/outdoor candid portraits, etc. while keeping the lens a little smaller and more affordable. It would still be a pretty big lens, but way smaller than the equivalent full frame 300mm f/2.8 lenses out there. Sorry I'm dreaming and going way off topic!
60mm is a little tough for a prime on M4/3. I loved the optics of the Sigma f2.8 but I found it hard to get anything inside of the frame. This kind of lens is for setting up a scene, not taking what comes.