In May, Google announced the availability of adding rich snippets to the Google search results through microformats and RDFa aided code. The two major complaints were not being about to:
(1) Know if you will be able to see the rich snippets in the Google web search results. (2) How they will look prior to them showing up in the Google web search results.
We still don't have the answer to knowing if they will show up for a specific site, without Googling it. But number two, being able to preview them, is now available with a new tool found in Google Webmaster Tools named the "Rich Snippets Testing Tool."
The tool can be accessed at google.com/webmasters/tools/richsnippets and you can plug in any URL (not just your verified sites) to see how the page looks with rich snippets on a Google listing.
The neat part is not just the preview, but it actually extracts all the microformats and RDFa data and shows it to you below the preview. I have a full screen capture at Flickr with this.
Extremely happy that Google added this tool. It seems like they have not announced it yet, and it is currently under beta. Hat tip to Beussery for spotting this first.
Forum discussion at Sphinn.