Unfortunately it proves to be quite a bit of hassle to do yourself. For some reason WordPress itself doesn’t have a Serendipity conversion filter in the import tools and Google has quite a bit of trouble finding the right one. So here’s the proper way to get your old blog’s content (including the second bit of the content, users, groups and comments) into WordPress.
The road starts here, with Technosailor’s version 1.1 of his importer.
You follow the road through the comments to Michael Tyson’s version 1.2 version which fixes quite a few bugs.
Then for the full neat importer, you go and find Carsten Dobschat’s version 1.3. The page is in German, don’t worry about that though.
For me, coming off the Debian Lenny version of s9y, it worked a charm, even when I re-exported a few times it didn’t create duplicate entries.
The final step is to re-organise your uploaded files. Michael Tyson has a script which does it for you here
Other notes when installing WordPress
I had to chown the wordpress/wp-content/ -R www-data and chgrp to the usergroup of the site. chmod 775.
touch wordpress/.htaccess and chown www-data, chgrp usergroup, chmod 755
Settings -> permalinks choose custom structure andfill in /%category%/%postname%/
The RSS feed address is http://robin.tripany.com/wordpress/?feed=rss2
Add the Blubrry Subscribe Sidebar
Category Icons is used to add… well…