Laura, it is just a few guests, and the problem is with what they write as guests, not simply that they're guests. Unfortunately, they've ruined it for other guests.

You'll be able to post whatever you want as a guest until Max changes things. There's a whole section in the FAQ on benefits of membership. You can send personal messages (PMs) to other members, you can trace threads you want to go back to, and you can participate in the auction.