Thanks for posting this thread. It helped me troubleshoot a problem I was having with Kate Glasis’s sideblog 3.4 after updating to wordpress 2.0.4.
After (re)activating the sideblog plugin, the widget was not available in admin/presentation/sidebar widgets. After reading here, I found the category I had assigned to the plugin (asides) was no longer checked (in admin/options/sideblog). Once the asides category was checked the plugin option appeared in the sidebar widgets.
