I found the HaloscanMacro plugin which uses Haloscan as support for comments in blogs. You can now leave comments everywhere, using the ‘Comments’ button that’s available on each tiddler, after the post date.
There is just a little problem: it doesn’t work smoothly with the BlogPlugin, so the tiddlers opened on the first page don’t have that button (yet – I’ll look into it). If you want to leave a comment or see if there are any comments on a tiddler that was opened automatically at start-up, you’ll need to close it and open it again.
That’s all for now. Go forth and comment.