Timo Schlueter

TagMeta generates meta keywords using your most used tags. 
It automatically gets the 10 most used tags out of your 
blog posts and pages and puts them into a valid meta- 
keyword string. This string then appears in the header of 
the home page of your theme. If you want to add tags per 
post, i suggest youre going to use the Headspace plugin.

TagMeta

TagMeta generates meta keywords using your most used tags.

fred91

Simplicy SEO
Simplicy SEO will allow you to optimize your SEO for your WordPress blog plugin itself supports the following tags:

Home page, page, article
<ul>
<li>
Meta tag keywords
</li>
<li>
Meta Tag news_keywords
</li>
<li>
Tag title
</li>
<li>
Meta Robots Tag
</li>
<li>
Meta tag description
</li>
</ul>

category archives
<ul>
<li>
Meta tag keywords
</li>
<li>
Tag title
</li>
<li>
Meta Robots Tag
</li>
<li>
Meta tag description
</li>
</ul>

Keywords archives

<ul>
<li>
Meta tag keywords
</li>
<li>
Tag title
</li>
<li>
Meta Robots Tag
</li>
<li>
Meta tag description
</li>
</ul>

Advanced options

-Meta tag creation
<ul>
<li>
Meta Tag author
</li>
<li>
Meta Tag Contact
</li>
<li>
Meta Tag copyright
</li>
</ul>
Geotag meta tag

<ul>
<li>
Meta geo.region
</li>
<li>
Meta geo.placename
</li>
<li>
Meta geo.position
</li>
<li>
Meta ICBM
</li>
</ul>
Facebook Open Graph 

<ul>
<li>
Meta Tag property app_id
</li>
<li>
Meta Tag property admins
</li>
<li>
Meta Tag property og: url
</li>
<li>
Meta Tag property og: site_name
</li>
<li>
Meta Tag property og: description
</li>
<li>
Meta Tag property og: type
</li>
<li>
Meta Tag property og: image
</li>
</ul>

Articles & Pages

<ul>
<li>
Meta Tag property og: url
</li>
<li>
Meta Tag property og: title
</li>
<li>
Meta Tag property og: description
</li>
<li>
Meta Tag property og: type
</li>
<li>
Meta Tag property og: image 

</li>
</ul>
French language

Simplicy SEO

viewed Requires at least: 3.0 Tested up to: 3.7.0 Stable tag: 4.3 License: GPLv2 or later License URI: http://www.gnu.org/licenses/gpl-2.0.

TagMeta vs Simplicy SEO