SEO Plug-ins

• All-in-One SEO Pack – It seems like this is pretty much the industry standard for SEO plug-ins. It handles titles, meta, keywords, etc. And allows you to adjust them on each individual entry.
• Excerpt Editor – This will automatically create an excerpt from the post and/or page. This is important for any themes that use exceprts like Thesis. Excerpts help with SEO and minimizing duplicant content on archive pages.
• SEO Smart Links – This will automatically create contextual links within your content to either appropariate pages or to a list of keywords and pages that you create.

Social Networking Plug-ins

• Sociable – Best looking “share this” plug-in.
• Wordbook – post your blog updates onto your Facebook account.
• Twitter Tools – post a link to your recent blog post on your twitter account.

Content Plugins

• Post-Plugin Library and its accompanying plug-ins – This will allow you to post a list of recent posts, similar posts, and/ or popular posts at the end of your posts or pages. It also allows you to insert a list where you want it.
• Widget Logic – Controls which widgets show up where based on WP’s conditional tags.
• WP Greet Box – Show a message at the top of your page depending upon which site the user is coming from. Ask a Delicious user to add to their account, or a Google user to add to subscribe to your feed. This is similar to the “What would Seth Godin do” plug-in but better in my opinion.
• Zemanta – When you’re writing your posts, this plug-in sits next to the box and offers up images and links that you could link to. Drag and drop an image in or click to add links.

Administrative Plugins

• WP-CMS Post Control – This plugin allows you to hide unwanted items on your write pages for both posts and pages. Cleans things up a bit and keeps your writers, authors, etc. focused on the things you need them to fill out.  (Example: I hide everything except the SEO stuff they need to fill out.)
• Google XML Sitemaps – This will automaticaly build your sitemaps out for you and submit them to Google.

That’s my list of useful plug-ins. And I am always adding new ones and testing them out. They have to be easy to use, easy to set up and easy to understand.

What are some of the plug-ins that you’ve found most useful?