Rich Snippets look like a good tool for the webmaster's toolbox.
Do you know of any way of integrating Rich Snippets into Wordpress?
To be clear, the Rich Snippets tool is purely for testing what the formatting/markup of your content is already. It does nothing on its own.
Most of the markup that the tool is looking for is usually baked into a theme. WordPress helps this along a little bit by incorporating parts of the hAtom format into the
There may be plugins that augment those
I often use the Advanced Custom Fields plugin to add more granular data to my WordPress sites. This lets me markup the specific pieces of data in theme files. (I wrote a blog post about marking up a People directory that the Rich Snippet tool can interpret. I've also done a business directory in a very similar way.) For the ACF fields, I like to use the vocabularies and markup specified by Schema.org, which is created by a consortium including Google.
Depends on what exactly you're looking for & how customized output. However, here are some plugins to get started. Hope this helps
http://wordpress.org/extend/plugins/gd-star-rating/ (This one is more widely used. Good for review-type site/blog)
Or, more can be found here http://wordpress.org/extend/plugins/tags/rich-snippets
Update back with the ones you find useful for others to know as well.