Summaryblogging, movabletype, spam
Wow! I just upgraded to Movable Type 4 and my comments have gone south.
For some reason, mt-comments.cgi is very slow and is taking gobs of memory and CPU. That, combined with spammers hitting the script as soon as it's executable means that the server load goes through the roof and things stop working. I tried some anti-spam things--even requiring authentication--but they all require that mt-comments.cgi run and that's not acceptable, as slow as it is.
Then there's the issue of friction. I've liked not having authentication for comments so that people can comment with as few speed bumps as possible. Discus requires authentication--on their site.
I'll keep digging into the slowness of the MT comment system. Doesn't seem right and there's not much on Google about it, so it's probably something local. Ugh.