I've upvoted for sharing information on this news. Thanks, I'm busy trying to sign up people and wouldn't have known that they cannot do it.

However I'm wary of this approach. Unlike Pinterest, potential new sign ups are missing out financially by being excluded. This could cause resentment if it's a deliberate ploy. The door could be left ajar for a competitor to exploit.

I hope it's a precaution... or a very temporary ploy to drum up a bit of hype.