Very important for SEO WordPress Plugins :
(1) HeadSpace (http://wordpress.org/extend/plugins/seo-slugs/)
(2) SEO Slugs (http://urbangiraffe.com/plugins/headspace2/)
(3) Twitter real time search scrolling (http://gopi.coolpage.biz/demo/2009/08/10/scroll-twitter-realtime-search/)
(4) FollowMe (http://wpburn.com/wordpress-plugins/wp-followme-plugin)
(5) SEO Friendly Images (http://www.prelovac.com/vladimir/wordpress-plugins/seo-friendly-images)
(6) Yoast Breadcrumbs (http://yoast.com/wordpress/breadcrumbs/)
(7) Meta Robots WordPress plugin (http://yoast.com/wordpress/meta-robots-wordpress-plugin/)