We have had several requests for a medium of communication on Coalriverpix, so members can post comments and ask questions about pictures. I am trying a blog software called WordPress. It has several advantages, including flexibility and security. The disadvantage is that each member has to be given privileges to make posts.
I am also looking at a “bulletin board” software called PHPBB, which is quite a bit more complicated to set up, but lets anybody post comments or start new topics. I’ll let you know how it goes!