"Decategorizer" removes 'category base' from your permalinks. Quick setup and no editing required. 301 redirections are added automatically.
THIS PLUGIN IS NOW OBSOLETE,PLEASE SWITCH TO 'WP NO CATEGORY BASE' PLUGIN
Go to http://skyphe.org/code/wordpress/decategorizer/ for the explanation, thanks!
"Decategorizer" will remove the category base from your category links, and turn your category URLs from something like "http://yourdomain/category/news/" to "http://yourdomain/news/".
301 redirection for old category links added automatically;
works with most permalink structures (please e-mail me or leave a comment on plugin's site if it doesn't work for you); you can safely use variables in your category URLs (http://yourdomain/news/?var=val); sitemap plugins compatible; it works with multiple subcategory links (http://yourdomain/categoryname/subcategoryname/subsubcategoryname/)
"Decategorizer" needs John Godley's 'Redirection' plugin to work and it will disable itself if Redirection is not installed. Redirection version 2.x. is recommended (Last tested with v2.1.9)