There is an email discussion list about RST. It is hosted by the LINGUIST list. It is initially an unmoderated list, managed by Maite Taboada. To sign up to receive the discussions by email and be eligible to submit comments, send a message to

LISTSERV@LISTSERV.LINGUISTLIST.ORG
with
SUBSCRIBE RSTLIST yourfirstname yourlastname

in the body of the message. Use whatever full name form you want people to see.
Addresses of RSTList subscribers will not be made public. However, if you have signed up and you send a message to the list, that will expose your address.

Alternatively, you can sign up here: http://listserv.linguistlist.org/mailman/listinfo/rstlist

The archives of these discussions are available online.