Well, I’ve been running Akismet for a few days now and so far it’s been flawless. I’ve had a few legitimate comments and a dozen spams. Akismet has caught all of the bad ones and none of the good ones. Excellent work!
I believe Akismet is working like gmail’s spam filter which, along with its own algorithms, takes the spam reports of other users and uses them as indicators of spam. It’s distributed and thus quick acting and far better than any single algorithm or single person can achieve.
If you have wordpress, you owe it to yourself to try out akismet!