Here is their Facebook page: http://www.facebook.com/pages/Sherat...44293882275306

By all means, let people know what happened yesterday - write on their wall but be careful to post only factual information, not even opinions. Hopefully, those poor people, especially the mom and young daughter who were also left stranded and presumably, others as well, will see this and back up your story by posting there as well. This will allow people who were dealt with in such unethical manner to connect. If 10+ guests all confirm they were told the exact same excuse when their prepaid room was canceled without proper notice, you may even have a case to submit a complaint to the relevant consumer protection agency should the hotel still tries to deny any wrongdoing.

You will also be doing the public, outside of the little corner here on FT, a great service by warning them about such unethical practices.