With the help of Serban Constantinescu (that recently joined the project) the forum module for gallery 2 is at its second (but still rather beta) release, we are now at version 0.1.6.
Please find the new project page here: http://galleryforum.sourceforge.net/
and an experimental demo site here: http://galleryforum.abelvedere.com/main.php
Generally users of the Gallery2 photo gallery that want to have a discussion forum on their site have to embed the whole gallery into a 3rd party forum or find other solutions, this module, currently in beta version, provides an alternative for all the gallery2 purist that don’t want to embed their gallery.
I am releasing it today, I hope you will find it useful.
Find more details: here