Interesting bit of trivia: Radio UserLand's comment system will only display a maximum of 125 comments for any given entry. Robert Scoble ( The Scobleizer Weblog) found this out the hard way - his EU decison post has received 137 comments so far.
UserLand CEO Scott Young says this is by design:
Its true. The commenting system has a defined limit for each each comment window. We had a problem with a malicious user trying to post extremely large messages in order to disrupt some Salon Blogs, so this restriction was added. Its not a bug, its a feature. ;-)
Side note: I wonder if trackbacks suffer from this limitation as well?