I would like to see what it will do with an L lens. The sample pictures posted by Canon are lacking in a few areas IMO, but they are with the cheap kit lenses.

I could see a place for a higher end mirror less camera. One of those areas would be Macro, for the most part I use live view for Macro. Landscapes would be another.

If I were still using a crop body, I could see a use for this body if the IQ is as good as the Crop DSLR's now.

I think the marketing here isn't to get DSLR owners to buy the camera, although it might be a good side effect. I think the logic with Canon is to give users of this camera the option to buy more expensive lenses. It gives a smooth transition in marketing, kind of like going from a rebel to a 5D II. While you can't take your EF-S lenses, most people who are ready for the move already have lenses they can use on FF. Same thing, if you buy this instead of a point and shoot, some day it may make the step easier for you to go to a DSLR.

It looks as if it might be better for making movies, using the EF lenses we have now. That might be a reason to buy it as well.