Edited June19/06 to remove Wordpress Themepark and change it to the Wordpress Theme Browser, which the former owner of Themepark is now administrating.
I recently created my very first Wordpress theme that I wanted to offer for free to the world. After uploading it to my blog, and tagging it with Technorati, and adding a screenshot with tags to Flickr, and adding some social bookmarks. I thought I had better do some research to find out where else I could submit my themes for the widest distribution.

1) The Wordpress Codex is the best place to start. All you need to do is register for an account, then edit the appropriate category in the wiki format to add your theme. The result is an instant PR7 link to your site.

2) Wordpress-Themes.org has a flashed-based file upload utility that is kind of cool. It’s a small list right now, but it looks like it has a lot of potential. Theme page currently a PR2

3) Leave a comment on How to Blog’s list of 875+ free themes for Wordpress and you’ll get some traffic from the comment section right away. And hopefully you’ll get added to the next update of the list. The list is PR5, and the comment section doesn’t appear to use the nofollow tag.

4) BloxFlux Theme Directory requires registration and a screenshot that’s 640×480, but if you jump through the hoops, your theme is added instantly. The theme page is a PR7, but your link will be on a unique page for your theme. Based on the directory structure, that page is likely to get a PR4 or 5 when Google updates again.

5) Wordpress Theme Browser (PR7)takes an uploaded zip file of your theme from your hard drive as a submission, automatically creates a screenshot and grabs the theme info from the style.css file. Very slick, and instant. Be sure to link to your site from the style.css for best effect. Now that this site is up and running, the Wordpress Themepark is offline… I think that leaves an opening for another site to come in and start with some new innovations.
6) The Open Directory Project seems to be listing only those sites that have multiple themes, but if you can make one, you can make two… and the ODP gets replicated at Google as well as other high-traffic sites.

7) Smaller link directories like the one found here

WordpressTheme dot com (PR5) seems to be down for the count, but it might be worthwhile submitting your theme via the contact form

9) Not yet fully functional, it seems, is wp-themes.org (PR6), where you can host your theme, and have it displayed wiki-style, like wp-plugins but for themes. Keep your eye on this site.

Anything I missed? Add a comment.