I think it would probably be something of a nuissance to require Community in order to get the feature in Gossamer Forum. I think there's no question that if you want _just_ Gossamer Forum, and no integrated login with other programs, GForum alone (i.e. without Community) is probably a better option.
Whether or not Community should/will have messaging, however, is a completely seperate issue.
Jason Rhinelander
Gossamer Threads
jason@gossamer-threads.com