I have absolutely no problem whatsoever riding the sidewalk. It's legal here, it's deserted and it's way safer than mixing it up with cars going close to or over 100km/h on some portions of my commute. Most days I pass not one pedestrian on my commute, there and back. If there are pedestrians I'll slow way down, ring my little bell to let them know I'm coming and pass them safely.
I'm a year round commuter, in a place where it means something (not that it doesn't mean something in Ottawa). I also mountain bike, ride road bikes and fixies. I resent the allegation that riding on the sidewalk makes me any less of a cyclist. I'm fully capable of riding on the road, but it would be stupid to risk my life mixing in with high speed traffic when there's an empty sidewalk right next to it. The only downside is crossing streets where I have to be more careful of turning traffic, but at least I have some degree of control there. In comparison, my influence on whether I'm rear ended on the road is negligible. Oh, and just to be clear, on the deserted sidewalks where I can see far and wide, I go flat out.