Andy Barr has the latest on the story a Sarah Palin "note" removed from Facebook earlier this week. Palin's post, covering her objection to the building of a mosque and Muslim community center blocks from the World Trade Center site, seems to have fallen victim to Facebook's automated system for removing posts from the site in response to user complaints.

But worth noting is that another factor in the Palin take-down is the interplay between Facebook's architecture and the mechanisms that drive the microblogging platform Tumblr.

If you're not familiar with Tumblr, it might help to think of it as what would result if Twitter and Blogger were to breed, a content platform makes it trivially easy for anyone to share links, excerpts, photos, and more. Brian Ries, a Brooklyn social media strategist and writer, seems to have kicked off the effort against Palin with a two-line post on moneyries, his Tumblr blog, that read, "Help Report Sarah Palin’s Ground Zero mosque note to Facebook for being 'Racist/Hate Speech.' Click-through to do it."

That's were Tumblr's "reblog" feature came in. That feature allowed fellow Tumblrs to repost Ries' call to action with just a few clicks. In short order, more than 750 reposted or "liked" Ries' directions on how to report Palin's post to Facebook as offensive content. "The same way YouTube embeds make it easy for a video to become a viral hit," says Tumblr, "the 'reblog' button on all Tumblr posts allows a meme to spread rapidly across thousands of blogs with just a click."

Tumblr's reblog ability to spread a meme rapidly seems to have worked as described. Ries was quick to give credit to the "Tumblr community." He addressed a note to that audience that read, "I’m pretty sure we f___ng did it! 756 likes and reblogs later, Sarah Palin’s Facebook note “has either been deleted, or does not exist.” SHE HAS BEEN REFUDIATED!!!" [Cleaned up a bit. Ours is a family blog.]

From there, the swarm of complaints seems to have triggered Facebook's automated pull-down mechanism.

Facebook declines to say just how many complaints it takes to trigger a post deletion. That's a reminder of how much control the company has over the venue in which Sarah Palin and others have chosen to express themselves. But the company does concede that the take down of Palin's post was automated, the outcome of a numbers-driven process rather than human review. "The note in question did not violate our content standards but was removed by an automated system," said Facebook spokesperson Andrew Noyes in a statement. "We're always working to improve our processes and we apologize for any inconvenience this caused."

Other social content platform's do things differently. We reported yesterday, in the context of radio host Alex Jones' campaign against YouTube, that while a single "flag" by a user is enough to send a video to YouTube's human reviewers, ultimately a person makes the decision on whether a video stays on the web or not.

Tough questions about how social media services handle who can say what, when, and over who's objections, are probably only going to gain steam as what we might call the Silicon Valley community ethos that these sites were built upon runs up against the harshness of the political world.

Bonus: A video explanation of how Tumblr's reblog feature works --