I had thought for a while about turning the current DP design into a WordPress theme, but because my love affair with Tumblr has since blossomed, and because I've actually received a couple of requests for just such a Tumblr theme, I went that route instead. Here you can go get the brand-new Deliberatepixel Tumblr Theme.
Creative Commons-licensed, it's free to use, share and modify as long as you give credit and make no money off it. If uber-minimalist doesn't fit all of your Tumbling needs, I'll have ready very soon a full-featured version of the same theme with tag, following and date support, plus designated spaces for about info, Twitter feed display, Disqus comments and link lists.
If you try it out, let me know - also let me know if you run into any issues so I can correct them in newer versions.