Data says otherwise, at least based on Japanese data from 2012. If you know data for other markets, please link to it:
In Japan, Canon had almost 29% of the total interchangeable market. Nikon had 25%. But, 1/4 of Nikon's sales came from the Nikon 1 (again in Japan). So that would put them at more like 19% just for DSLR cameras. Canon only had 2% of their sales come from the EOS M, so their DSLR figures would be in the 28% range.
So 28% vs 19% in Japan for DSLR in Japan. Is Canon really losing DSLR crown?
Yes, the EOS M is a flop, even against the small sensor Nikon 1, but just speaking in terms of DSLR sales, I don't know if I can agree with your doomsday predictions. Japan is a big enough market, I think we can use it as a reliable example.
The CanonRumors web site reported the same data, with the additional comment that,
So, I guess Canon's pro cameras aren't as big a disaster as commentary on POTN would have you believe.