Yup , apples and oranges .... Both give great images , but each has its' own advantages . I like the M9 because it's small , unobtrusive , and , being manual focus , forces me to slow down , think a bit ,and get a grip on what I'm trying to do.Can't blame the camera if I screw up . A great walk around the city piece of gear. It's pretty much my M6 with digital guts .My Leica kit ( camera,3 lenses ,tiny flash , extra battery in a small Domke 5XA (?)bag ) ,weighs a shade over 5 lbs.I can carry it around all day with no problems . It's what goes into my carryon when I'm travelling on bus or train.
I use the Canon stuff more mostly because its more versatile . It'll go wider than I can with the M9 , and longer , has higher usable ISO , will do macro , and can use polarizers ,ND grads and such without any drama . I also have no guilt over exposing it to dust , occasional water spray , and temperature extremes . And if I drop it I won't have a coronary, I'll pick it up and keep on going .Both bodies ( I have a 5D2 and a 50D ) seem to be pretty much bulletproof.
But they're big , and heavy, once you stick a 24-105 on it. I also find I take a lot more shots with the Canon , but at the end of the day I won't necessarily have more keepers. My Canon gear (5D2 ,17-40,24-105,100-400 , 430EX flash , plus the usual CF cards and spare battery) , in a Domke F4AF bag goes
around 18 lbs. No way I'll walk around with all that stuff , this only goes with me if I'm flying as my carryon , or driving .
A somewhat convoluted reply , but the best I could do . Guess it boils down to grabbing the gear I think will work best for me at the time.