Changes to groups

1. If you mention a !group, even if the notice is not distributed to the group, the name gets linkified as a tag.
2. At the group admins' discretion, non-members can be allowed to post to a group. The default is set by the site admin. Example use case: a !support group for asking for tech support on Identi.ca.
3. At the site admin's discretion, groups can share the same (logical) namespace as users. In this case, you can't have a group named "foo" and a user named "foo".
4. At the site admin's discretion, "@name" will send a group message, just like !group. (This will clearly work best when there's no confusion whether "@name" is for a user named "name" or a group named "name" -- that is, when 3 is enabled.)

Originally posted by Evan to the mailing list