I saw the notice. I am not quite clear on the difference between the three other than 2 are M mount. There is the difference in minimum focus and material. It did not mention about the lens coatings. Typically there is a single and multi coated version
The fact that they offer the lens in a vintage and a modern M mount version is intriguing in itself - I'd really like the Heliar 40mm f/2.8 in that style (I own the current LTM version - fun, but fiddly).
That said, ever since the arrival of the wonderful Voigtländer Ultron 28mm f/2 II Aspherical, a lens of this type is a much tougher sale - so, we'll see how it's received.
Nevertheless, it's a nice addition for all who want something even more compact than the Elmarit-M 28mm f/2.8 ASPH - and I'd not be too surprised if the new lens turned out to be more or less its equal optically. The Ultron is simply fantastic and easily competitive with the (bigger and hugely more expensive) Summicron-M 28mm f/2 ASPH.