Thanks, everyone, for the kind words !
I thought of an automatic water-feed, but the freezing conditions would require a heated line and that just added too much complication for a project I wanted to deploy quickly. Definitely in the works for next winter, though. Same for the motion detector camera.
I have seen squirrels, a cat, and birds drinking in daylight hours ... heard sounds in the night, and seen lots of various tracks (raccoon and skunk for sure, maybe opossum) when there is fresh snow in the morning. Lots of takers too, the bowl typically needs refilling 2 or 3 times in 24 hours.