The problem with the M9 is: cost, poor high ISO performance, and lack of lenses :-).
Yeah, the price is the kicker. Manual focus is a problem for some, although I am old school and I manual focus a lot, so it does not bug me. The guy who let me fiddle with his M9 commented that he thought the shots that he took with it came out sharper than equivalent shots with his 5D2. For him, the smaller lenses for the Leica appealed to him because of their size. I got the sense that his 30 years of shooting Canons (with big glass) took their toll on him.

@briansquibb: love the shots.