Well just after I posted about Vista, Wordpress managed to go totally toes-up. I did the usual fiddles (deleting htaccess and recreating permalinks, deleting all files and reinstalling wordpress, etc.) and they didn’t work, and to be honest I have little patience with malfunctioning software. Long story short, I’ve switched to Textpattern and I’ll be setting it up with tag plugins etc. over the next couple of days.
UPDATE: OK, I’ve got all necessary gubbins installed, I’ll migrate the Technorati tags from old posts tomorrow, and IIRC from last time, Textpattern turns comments off on imported posts by default. That will require more phpmyadmin fiddling to fix, but shouldn’t take long.