Of course, because this is Nintendo, there are some inherent protections within the non-friends play. When you choose to play with "anyone," you will not see your opponent's name, and there will be no records kept of your victories (or your painful losses). But at least you can play, so we're not going to complain. This latest update also cautions that online play across continents may be slower than a match with someone relatively close by. In the end, most of the focus seems to be on friends-only play, but that was to be expected, and we're frankly excited that the "play with anyone" feature was added at all.
[Thanks to everyone who sent this in!]