Earlier this week I decided move an old self-hosted WordPress blog into Tumblr and discovered that there really weren’t any tools to import your existing WordPress content into your new Tumblog. So I built one.Import a WordPress blog into Tumblr
I’ve been meaning to write something that does this myself. I might fork this code and tweak it.
UPDATE: Apparently a lot of people have been working on this. Here are some other approaches: