I upgraded my blog from 2.1.3 to 2.2, and I noticed that for the past week, no comments have been able to come in, even spam ones (and I usually get 50 or so spam comments a week). I played with my plugins and found that if I disabled Akismet, I could post a comment. If it's enabled, posting a comment produces a blank white screen. It's not the dreaded white screen of death, because the blog still works, but the comment was never submitted.
This is Akismet 2.0, which is the latest. Also, when I try to go into Akismet Configuration in the plugin admin area, it tries for a long time and then doesn't respond.
Actually, I just noticed that my other blog on this server, which is still running WP 2.1.3 also has this exact problem. So it's not caused by my upgrade. What could it be, then?