Robert B. Parker's official site has added a section of related links, describing Dodd Vickers's Spensarium Yahoo! Group as as "THE Robert Parker forum. Lively, smart discussions of all things Parker."
Not listed is Spenser's Sneakers, the group I formed after leaving Spensarium.
Few people know that my first moderating experience came in January 2000 when Dodd asked me to oversee his group two days into its existence. I tried to foster in-depth discussion and genuine dialogue about Parker, but some Spensarium members reacted strongly against any criticism of Parker.
In early June 2001, I decided to leave and form Spenser's Sneakers so readers who wanted to go in-depth wouldn't butt heads with those who didn't. Dodd erroneously saw this as competition for his list and deleted my parting post to Spensarium/invitation to join spensneak.
Rest assured we do exist.
UPDATE (08/28/06 10:00 AM): A friend convinced me to let Parker know of spensneak via his Web site. Stay tuned.