Short answer: probably not.
If you browse around the net enough you'll see lots of people claiming that Olympus or Sony or Panasonic or Samsung are doing well because their mirrorless sales have some significant percentage of the interchangeable lens market (where their DSLR products did not).
The market that has most accepted mirrorless cameras is the Japanese home market, and interestingly, it's the market for which we can easily get fairly reliable weekly, monthly, and annual sales numbers for interchangeable lens cameras bought at retail (as opposed to "shipped by maker"). You find four mirrorless cameras in the top ten list (E-PL2 at #3, GF-2 #5, NEX-5 #7, E-PL1 #9).
Nikon believes they should see all three of their consumer DSLRs in the top ten. And they do: #1, #6, and #10. The #1 D3100 sells twice as many units in Japan as the #3 best mirrorless camera, at least in/thru May of this year. Overall, the D3100, D5100, and D7000 account for 22.5% of the interchangeable lens camera market in Japan. Add in the other models and we're pretty close to Nikon's traditional 30% share (the quake hurt D700 and D3s/D3x sales, as there weren't enough to sell for at least one of those months).
Canon, on the other hand, ought to be seeing real trouble in this year's numbers. They've only got two models (both KISS/Rebel) in the top 10, and command only a 16.3% share with those models. In other words, Nikon's consumer models continue to do decently, with only a bit of erosion from where they've traditionally been, but Canon appears to be losing ground to the mirrorless boys. Someone has to be panicking at Canon headquarters, while at Nikon they're looking at those same numbers and not worrying that they have to rush into mirrorless.
Still, the trend--at least in Japan--is very clear. If you run a moving average on mirrorless sales' share of interchangeable lens cameras in Japan, the slope of the line is relentlessly upward. Not at a fast rate, but one that is nevertheless scary to the two traditional DSLR leaders. Throw things like the fast focusing Olympus mirrorless models to be announced tomorrow and the Sony A77 into the mix for the second half of the year, and we're going to see plenty of market share movement, I think. Nikon will counter with a D400, and eventually a low-end mirrorless. The big question is what will Canon counter with?