The basic idea for something like this is that one person issues a seek and then if another person issues a similar seek they are automatically matched together.

Public matchmaking / lobby is also related to the cheating issue mentioned in another thread. We're holding back on this for the time being.

I think the whole thing is tricky to solve, but it's solvable and solving it will help with other games as well. Limiting the games to people that know each other will dramatically reduce the number of participants. MIght work while the site is small, but to get wider adoption you'll probably have to go beyond people that trust each other in real life and will have to put in some form of reputation system.

That's true, it's a challenge we'll have to face. I mentioned reputation in the other post, there might be a few orthogonal components to this which, combined, can be used to solve cheating.