I've just finished a ruby script 'parse-bookmarks.rb', which reads in a mozilla-style bookmarks.html file, generates a flat list of name/url pairs and assigns tags to them based on the folder heirarchy they belonged in.

It then checks each generated tag for invalid characters and lets you offer alternative ones. Finally, it connects to delicious and adds each URL, with a second delay between each add (by request of the admin).

I've just emailed the delicious guy to let him know about it, assuming there's no objections I'll release it ASAP.

see the results of my import.