Hey all - just a couple answers based off of my experiences:
Javaslinger, if you get a blank dialog box during a Pantheon game search, you will also have a "connection info" box in the bottom right corner. Click on that box and you'll see another box pop up like the one shown in the first post. You can watch as the other human players connect with you and each other. It's not necessary to do that, but it's essentially a countdown... and you know what's going on instead of staring at a boring screen.
The player names that do not have any connection info are computer controlled characters. Every Pantheon game seems to need 6-8 players, but only allows 4 human players at the moment. Once every human character has connected to every other human character, the game will start.
One last thing: if anyone in the group drops during the connection process, the game will not start. The game doesn't seem to be able to find a new player for the one that dropped, so you'll just sit there indefinitely. At that point it's probably a much better idea to just cancel and try again. I've had to do this a few times in a row because of impatient players that would have been able to play if only they'd waited another 10 or 20 seconds.
Hope it helps, and I hope to see you in game 
