So, CoComment is out. I want to join the beta. 
But they have an invite code on it. I hate these things. Why bother?
If it's just for marketing (which the CoComment folks say it isn't), then fine.
But if the service is as good as it sounds, then you don't need to market it. We will market for them.
Instead, here's a better solution. Let people sign up, but have them trickle in. They can fill in the join form, and confirm their email. They are then added to the 'wait' list. Let a few hundred in, test away.
Then when you're happy, let a load more in. Repeat this process until you're ready to go.
Then, and this is important: remove the damn beta labels.
