Semantic Tags plugin provides you everything you need to create and semantically markup your Tags.
How much does the Semantic Tag Plug-In cost?
Nothing, this is a free Plug-In.
Do I need to use other WordPress.org tag widgets?
No, semantic tags are the only tag markup you’ll need.
Do I need to add “keywords”?
The tags must be relevant to your post, as with the markup inside each tag. Providing they are, you do not have to tell the search engine what keywords you are targeting with your article.
Can I really use multiple rel attributes?
Yes, as long as you leave a space in between each attribute.
Can I use this Plug-In for Authorship markup?
Theoretically, yes, if you were handy with editing the code. However, we do have a similar Plug-In coming soon that will add rel=author for you.
When should I use the “nofollow” attribute?
If you're not aware of the benefit of followed (DoFollow) outbound links or if you do not fully trust the reputation of the site you're linking to, then use "nofollow" as your first rel attribute. Other attributes can be added after "nofollow".
If I add a tag to my post from the Sidebar Widget, will it still work? Yes, all of the tags, once saved, retain all of the information you enter about them. However, if you change the setting of a tag to suit a particular post, those changes will be reflected everywhere you have that tag appearing on your website.