The shortage of Leica M lenses appears to be fading. Dealers are reporting that shipments of these lenses are very much improving. Even the 35mm Summilux f/1.4 is showing up again.
Leitz reported a while ago that they have hired additional personnel. Apparently the sales increases over the last months resulted in Leica not being able to manufacture enough lenses for timely shipments to their dealers. This has not only resulted in hiring additional personnel, the direct result of which are the increased shipments of lenses that have been in short supply for a while. Leica is also considering keeping the Solms facility open, even after they move back to the new headquarter in the Leica Park in Wetzlar in 2013. Previously it was assumed that the Solms facility would be closed.