Hi, in March, a couple of Server Meltdowns due to comment spam forced us to take a bigger blog installation from MT to WP. We're talking about Comment spam in the magnitude of a couple of thousand comments a day. And now? The System is up and running on WP for two weeks, and there's only been 93 Akismet identified spam comments so far. I find this stunning, and I don't really have any explanation. The URL is the same, but, of course, the comment script's URL has changed.
So I'm assuming we're simply getting a little break until the spam bots have realised what to do. But that does apparently take longer than expected. So maybe dynamically, randomly renaming the comments scripts from within WP would be a useful way to protect from spambots.