I’m playing with the 3.2 beta of Movable Type as well. It’s definitely looking better, as SixApart finally brought back bulk spam filtering for comments and trackbacks (originally lost with the upgrade to 3.0). I’ve found that absolutely crucial for keeping my filters properly tuned.
It also looks like I’ll have an easier time putting in some of my other spam checks which would be a big help (rather than trying to modify the filtering software directly). I’m running Beta 4 on another test website. I’m not sure it’s quite up to production quality but it looks very close so I expect a full release in a matter of weeks.