stephan.gerlach

This Plugin lets you set some shortcodes and display content depending on what search engine the visitor came from and what the person searched for.
This way you can make sure you can show your visitor content they are looking for.

seKeyword

Display content depending on search engine and keywords

Purab

Boost your wordpress SEO: Full SEO features Meta Tags, webmaster tools settings, Social AuthorShip for Facebook, Twitter and Google Plus and XML sitemap
You can enter your meta keywords and description for your homepage.
This plugin will add different Meta description for each individual post as your excerpt of your post.
This will help your blog to rank better in google. You can easily increase your blog traffic using this plugin.
New Premium Features Added
WebMaster tool and meta tag added
Social AuthorShip meta Tags added for Facebook, Twitter and Google Plus
XML sitmap added
Following Sites are using SEO meta tags: 
Demo URL: 
http://wpapi.com
<a href="http://wpapi.com/how-to-use-seo-meta-tags-wordpress-plugin/" rel="nofollow ugc">Step by step installation instructions >></a>
Tested upto 4.0
<a href="http://wpapi.com/contact/" rel="nofollow ugc">Click here for customer support >></a>
<h4>Functionality</h4>
This plugin will add different Meta description for each individual post as your excerpt of your post.
<h3>Help</h3>
For help and support please contact us at contact [at] digcms.com 
<a href="http://wpapi.com/contact/" rel="nofollow ugc">Click here for customer support >></a>

Seo Meta Tags

Boost your wordpress SEO: Full SEO features Meta Tags, webmaster tools settings, Social AuthorShip for Facebook, Twitter and Google Plus and XML sitem …

seKeyword vs Seo Meta Tags