I had an original M, which i had enjoyed overall, but always longed for some sort of viewfinder. I eventually sold it to pick up an X-Pro1 which i have REALLY enjoyed, but i never bothered to buy fuji glass, and just shoot adapted FD lenses with it.
This may be enough to bring me back to the EOS M fold. i still love the idea of a mirorrless camera that can work natively with my EF & EF-S lenses and the rumor looks like it answers all my beefs with the EOS M design up until now.
Edit: i see there already is an EOS M rumor thread open, mods please delete this.