I bought the M8 in Jan 2010, M9 in early 2011, and M Monochrom in Dec 2012. I picked up a Nikon Df in Nov 2013, first day they hit the local camera shop. When these can no longer be repaired, I'll consider options. The M9 and M Monochrom both have the new sensors in them.
It's nice to know Leica is selling refurbished M9's. This will be the last of the CCD based cameras outside of the technical field.