Michael Feldstein “suggests”:http://www.elearnmag.org/subpage/sub_page.cfm?section=3&list_item=25&page=1 that the tendency of bloggers to link to other bloggers, usually done as a way of crediting them with the idea, tends to smother discussion or debate: “The very same hyper-linking impulse that makes it easy to pass along an idea with a minimum of effort also makes it easy to appear as if I’m agreeing with the post I’ve referenced when, in fact, I’m just deferring to it.”
From an academic perspective I think Cass Sunstein “got there first”:http://bostonreview.mit.edu/BR26.3/sunstein.html (though he was talking about Internet mediated discussion more generally). I know this is one of the things that bothers Habermas about the Internet (I asked him). Shanto Iyengar “disagrees”:http://bostonreview.mit.edu/BR26.3/iyengar.html.
Thanks to Jeremy Wagstaff for the link