How about having a field for adding text when creating game. When the game is joined by other members an extra form would be needed to be clicked through if the field contained text.
This field could be used to give background on the game and warn people if it is going to be slow etc. Its main purpose though would be to allow the creator to put up requests for things like RT, certain time zone etc so everyone knows what they are getting into.
If worried about abuse it could be implemented with a limited set of options (which might be ??examples anyone??) rather then free text.
