For months now, the top commentators list has shown Betshopboy‘s entry together with someone else’s, with no link and no separator.
The problem was that some of his comments had a URL attached, and some didn’t, and that apparently confused the plugin. Since he recently got his own domain, I went through the database and updated all the comments to point to the new URL, and the top commentators list now displays correctly.
This isn’t really a permanent fix, though, since the next person who doesn’t put a URL in when they comment will still show up incorrectly. I haven’t quite figured out why, but suspect an incompatibility with the theme.
I’ll put some time into figuring that out when the problem comes up again.