Somewhat wishy-washy title, I know.
But here's my point, I look forward to a world of stable URIs for intellectual content in which responses to scholarship and primary data are distributed around the Net.
A case in point, my NYU colleague Chuck Jones blogged about the digitization of some of Blegen's diaries by the American School of Classical Studies.
If you look at the bottom of the post, you'll see that he included the Pleiades URI's for both Mycenae and Tiryns.
It is now the case that a Google search for the Tiryns URI lists Chuck's AWOL post.
Assuming that ASCSA doesn't move that resource to a different URI and that the post remains available, stable URIs for Tiryns and Mycenae have now been permanently associated with the ASCSA resource. And that with the publisher of the information doing nothing. (Though it would be nice if ASCSA ditched the "index.php" from their URIs. See here.)
And note that I'm walking a fine line in this post. The Pleiades URIs that Chuck included explicitly in his post don't appear in the text of mine. I don't see any reason to clog up the Google search with this meta-meta-commentary.
By way of slightly living up to the title, my point is that such a decentralized "commenting system" should be encouraged. If you're able to link from your content to a stable URI that more-or-less represents the same concept, do so. And use such URIs when you're talking about other's people's work. That will encourage a distributed network of publication and response that is robust, open and encompasses many forms of expression from tweets, to blogposts, to more formal work, and beyond.