It's kind of odd. I'm a fan of the deeply saturated colors that polarizers can bring (I don't use them to reduce reflections so much except for making water more translucent). But in shooting the M8 and M9, especially with good lenses - the colors are already so nicely saturated that I find a polarizer relatively superfluous.
Then there's the variety of solutions, none of which are really "ideal." Perhaps for local use where you plan to shoot with it a lot... Less so for more "stop and go" shooting while on vacation or traveling, for example.
Consider some of the following shots - none of which used a polarizer. Now granted, the 28 Cron shots will exhibit some of the sky darkening effect simply because it's a wide angle (which increase the effect). But even the second shot, from the 50 Lux exhibits this (though granted, to a lesser degree).
M9, ISO 160, Summicron-M 28mm f/2 ASPH, 1/1500s @ f/5.6:
M9, ISO 160, Summilux-M 50mm f/1.4 ASPH, 1/1500s @ f/8: