Well, they both have AirDrop and I was in the AirDrop Finder window on both for at least a couple minutes as I went back and forth between the two computers, but neither computer ever showed the other computer with a bubble picture like it appears in the marketing, only itself at the bottom.
Good to know that they don't even need to be on a WiFi network to work. I guess I'll just try again when I get home tonight and see if it works.