One of the more interesting ones is the ability to add a public comment on any website that appears in a search result.  This appears to be directly from the StumbleUpon playbook.

As you can see above (see the Wikipedia link), a small bubble appears with lines in it after the search result.  By clicking on that bubble, you are provided a quick way to comment on a site (see second example above).

However, even more interesting are the arrows that appear next to the search results (see below).  By clicking on the correct icon, you can promote OR remove the item from your search results.  This appears right out of the DIGG playbook.

I think the bigger question for many search engine optimization folks is this: How will these user generated actions impact the listings of pages.   Or perhaps, how might they be manipulated to get certain websites to appear on the first page of Google?

What are your thoughts on this new change from Google?

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