Facebook announced some new WordPress integration today. This includes a new plugin called Facebook for WordPress. It comes with "social publishing features" and the following widgets (as listed on Facebook's developer blog) which have been around for some time:
While the comments plugin has been around a while, I find it noteworthy that Facebook is touting the "SEO support" as a selling point.
If you go to Facebook's page for the Comments plugin, the company says:
How can I get an SEO boost from the comments left on my site?
The Facebook comments box is rendered in an iframe on your page, and most search engines will not crawl content within an iframe. However, you can access all the comments left on your site via the graph API as described above. Simply grab the comments from the API and render them in the body of your page behind the comments box. We recommend you cache the results, as pulling the comments from the graph API on each page load could slow down the rendering time of the page.
As we've seen in the past, Facebook comments on your site can show up in Google search results. That said, the search value of comments, in general, is debatable. A while back, we spoke with Shoemoney's Jeremy Schoemaker, who spoke with a Google engineer friend about blog comments.
This was pre-Penguin update, when much of the industry focus was still on the Panda update. It was (may still be) worth considering how comments might impact a page's quality in terms of how Panda looks at content.
According to Schoemaker, the Google engineer indicated that if anything, it’s “diluting the quality score of my page” by possibly diluting overall keyword density. Another factor could be the few common comments that go through that are clearly spam send signals that the page is not being well maintained.
“So he said he did not see a positive to leaving indexable comments on my site,” Schoemaker told us.
Of course, no Google employee knows everything about Google. That's not to say this person didn't know what they were talking about, but one Googler recently indicated that Google didn't have anything called Penguin. It's just wise to keep a grain of salt on you with these types of things.