PhotoQ allows you to host full featured photoblogs with WordPress. The plugin is aimed at automating publishing of photos as much as possible.
With this newest update, PhotoQ is now also fully compatible with WPMU, so you can build your own photoblog community.
More information on this version: http://www.whoismanu.com/blog/2009/11/photoq-photoblog-plugin-now-for-wpmu/
Full description / documentation: http://www.whoismanu.com/photoq-wordpress-photoblog-plugin/
Download: http://downloads.wordpress.org/plugin/photoq-photoblog-plugin.1.8.3.zip