Just letting WordPress users and theme designers know about a website for finding, uploading, maintaining and displaying themes. ThemeBot.com is a site that specializes in showcasing themes for open source software. There are galleries for content management systems, blog and forum software.
It is free to join and upload a theme. New themes are featured on the homepage. A high quality gallery screenshot is created for you and your theme is added to the live demo. You can also subscribe to the WordPress download section with RSS to be notified when a new theme is added or an old theme is updated. Lot's of new features are in the works and the website is actively maintained.
The WordPress ThemeViewer is a great resource and ThemeBot can be used as a supplementary site, both for finding themes and for displaying themes. It is a great way to reach more users, since many people looking for themes from various platforms use ThemeBot.
Please let me know if you have any suggestions.