Hi all. I own an S90, and it's been a good camera.
I've been thinking about the EOS-M, have read and watched all about the auto-focus. I played with my S90, and it seems to me that the auto-focus speed is roughly similar. I have never owned a DSLR, only G and S series cameras, that's what I'm used to.
It seems that it just fails when compared to a DSLR, but considered as a compact, it's nothing unusual.
Another observation is that the touch screen appears to be far more efficient to operate than a bunch of knobs, yet this efficiency isn't appreciated as part of overall speed of operation.
So as a S90 owner, I may be happy with the EOS-M. I mostly look to a small camera to take on long hikes. The price drops are very enticing.