As always, a new version leads people to speculate...I'm working on some side-by-side images comparing the V2, V1 and Summilux ASPH. (non-FLE). In a carefully controlled test, the only difference I am seeing between the V1 and V2 lenses is a slightly smoother bokeh with the V2 lens. Given that the diaphragm blades appear identical, and appear to be identically placed, the only thing I can conclude is that a slight adjustment of the optical formula has helped--possibly a result of the changes to allow a .5m close focus.
Overall, both copies of these lenses are slightly sharper on the whole than my copy of the Summilux, even in the corners. That said, there is always sample variation--the first copy of the V1 Nokton I had was a good bit softer, and while my Summilux is very good, I know there are worse and better copies of Leica lenses out there as well.
The smaller size of the new V2 is very handy, although it's still bigger than the Leica. The V2 does have slightly better construction quality than the V1 lens. The overall feel is a lens that is "tighter" in construction, and closer in quality to the Zeiss lenses than some of the other Voigtländer lenses. The close focus change means that it has a longer focus throw than the V1 lens. The length difference is all but imperceptible, but the reduced barrel diameter is very noticeable, and makes the V2 lens seem much smaller.
Coding to correct for vignetting is important, unless you like the vignette. I have found that the best correction is using the v1 Summilux ASPH code, although it slightly overcorrects the image at the f/2-4 range. For those who like to hand-code their lenses on the M8 and M9, the groove on the new V2 lens mount is a boon.
Overall this lens is a great value--like most of the Voigtländer lenses. I'm working on a full write-up with a comparison of 100% crops. I'll post a link here in a few days when its complete.
Meanwhile, here's an image of OOF lights that shows the smoother bokeh of this lens--no busy lines in the OOF highlights, or harder edges.