Unfortunately, treating comments as nodes in response to nodes makes the database optimizations particularly difficult for the tracker. It's not impossible to make it run fast, but treating comments as special kinds of nodes takes much elegance out of the design. Robert Douglass wrote:
Since it came up, I'll draw everyone's attention to the nodecomment module which makes comments into nodes. Rather, it uses one node type to be the comment type of another node type. To me (and the other Lullabots) this makes a lot of sense. All that is needed is a 1:n mapping between a parent and its children and some special display. What makes the nodecomment module really special, however, is that the rendering of the "comments" is handed off to the views module (which is a requirement), so you could display your comments in totally non-traditional ways, such as in a table or in a calendar.
One of the most useful applications that this module has found is also the impetus for its creation: voting widgets in the comments that vote on the parent node. I'm creating a site, for example, where the comments are all ratings of the parent node, and each comment needs to have four separate fivestar widgets. To do this, the comment node type has four CCK fields from the fivestar module where the target of the voting is set as arg(1)... meaning the fields belong to the comment nodes but the votes belong to the parent node. Very cool.
We've had clients who have requests like wanting to promote comments to the front page, or rate comments, or categorize comments etc. This module fills those needs.
The release says it is beta, and I stick by that, but it is worth noting that this beta code probably serves 5 million page views a day or more on live (rockstar) websites.
-Robert