From an HCI standpoint this would be tricky, but it would be great to have a system for handling dupes and near-dupes by merging their comment pages. For instance, right now there are two articles about the recent demo of Metaweb/freebase. I commented on one of them, returned to the mainpage, and realized that the other (which also had no comments) was now higher ranked.
This raises a quandry as to whether I should cross-post, or just move on and hope that the discussion happens in the one I picked.
(Note, this is the harder case, of near-dupes: the two articles are different, but \begin{precog} most of the discussion will be about the product they reference.\end{precog} Hence it is semantically reasonable to merge their comment threads.)
So, as a oneliner: add a way to merge duplicate articles.
