So at this point, the X100 beats the EOS M in:
Anything the M has an advantage in? Maybe size, but is it pocket-able?
I dunno, I was originally looking at the Olympus EPL5...
Eos M advantages -
1. No need to learn a new menu system.
2. Ability to use your existing Canon lenses via adapter.
3. A Canon hotshoe, no need for additional triggers for off camera flash.
4. Pocketable (with 22 f/2 lens and large jacket pockets!)
5. Magic Lantern
6. Higher resolution
7. Larger screen with anti smudge coating that actually works (and it's touchscreen but this could also be a disadvantage)
8. Works with Canon RC-1, 5 and 6.
9. Has Touch shutter feature that allows you to select a focus point, AF and take a picture by tapping the screen. (Still not found a good use for this though!)
Of course some of these advantages are Canon user specific. If you already have Canon accessories. In a straight up head to head the Fuji wins. No contest.