There are many bloggers that use WordPress. If you have a self hosted WordPress theme than you need to download and install the plug-ins below. They’re specific to SEO, Pagerank, Performance, Backup, and Statistics. The Plug-ins:
SEO Title Tag: The most import plug-in for SEO (Search Engine Optimzation). This little plug-in re-writes your title tags so that spiders can index your site based on keywords within the tag. SEO Title Tag makes it easy to optimize the title tags across your WordPress-powered blog or website.
http://www.netconcepts.com/seo-title-tag-plugin/
WP-Cache: Speed up your WordPress theme! WP-Cache is an extremely efficient WordPress page caching system to make your site much faster. It works by caching WordPress pages and storing them in a static file for serving future requests rather than loading and executing calls to PHP.
http://mnm.uib.es/gallir/wp-cache-2/
Google XML Sitemaps Generator: This plugin generates a XML-Sitemap compliant sitemap of your WordPress blog. This format is supported by Ask.com, Google, YAHOO and MSN Search.
http://www.arnebrachhold.de/projects/wordpress-plugins/google-xml-sitemaps-generator/
WP Backup: Backup your WordPress easily and efficiently. You can have your backup executed automatically and sent via email or to a writable folder on your web server daily. I prefer to have it generate an email daily.
http://www.ilfilosofo.com/blog/wp-db-backup/
NoFollow: NoFollow Free removes the “nofollow” attribute from your WordPress blog’s comments (precisely from the author’s links) and/or from the comments text links and it inserts (if you want) an image band at the top of your pages with the phrase: “NOFOLLOW FREE” is a useful attribute to conserve pagerank.
http://www.michelem.org/wordpress-plugin-nofollow-free/
WassUp: If you like statistics you will love Wassup. WassUp is a WordPress plugin to track your visitors in real time. It has a very readable and fancy admin console to keep tracks of your blog’s users visits, current visitors online, visitors details and so much more. It comes with a “Spy” view in Ajax like the Digg Spy.
http://www.wpwp.org/
All in One SEO Pack: It’s all about SEO! This plugin does it all. Streamlined for some best practices for WordPress SEO. While it gives you many options the defaults reflect the settings recommended.
http://wp.uberdose.com/2007/03/24/all-in-one-seo-pack/
It’s important that you stay current with all your plug-ins. You can check your Plug-ins link in your admin console to see if there’s any new updates for any plug-ins you’re using.