Will bet money that that is not the sensor in the M9. Although it would make sense for Canon (or Nikon) to provide Leica with a sensor, I don't think Leica would go after one due to their relationship with Panasonic and Kodak.
Canon/Nikon could possibly do well to let Leica use one of their sensors, as it would help cover the R&D and the final product really wouldn't detract from their EOS sales. Essentially they'd be getting a share of a competitor's profits without losing market share. On the other hand, I'm not sure how tempting the prospect is to Canon, as the M9 sales would be a drop in the bucket compared to the sales of their DSLR's and point and shoots, but still, if the sensor is already developed, and they can get it into a market they're currently not tapping and not interfere with current/future products of their own, I don't see why they wouldn't.
Anyways, I don't think Canon is going to let another company use their new cutting edge sensor in their own cameras. I think it'd be bad for both companies, as whichever camera is cheaper, sales of the more expensive one would be hit by criticism such as 'Yeah but for $5000 cheaper you can get the same sensor of the m9 in the 7D'. Not 'a very similiar sensor' but the exact same one. They'd have to be different just to make criticisms just like that more difficult