I was invited and had heard that Google will send invites in to my account to give to others. I guess if they are not adding new accounts now, that may explain why invites that I can give to others haven't yet shown up. I hope they open up the spigot again soon.
I am planning on hosting another 'peek at Wave' session soon in Elluminate so that those as yet without an invite can see it and learn more about it. Let me know if you want me to keep you in the news loop for that.