This evening I noticed Facebook adding an iFrame to links shared in the homepage stream. The iFrame allow users to comment on a shared item without having to go directly back to Facebook. The iFrame also has an option to further ‘Share’ the item and add it to your homepage stream. All commenting and posting is done via the typical Facebook pop-up, aka leightbox.
Attached is a screenshot of what the iFrame looks like:

My friends profile picture has been blurred out but her comment on the posted item can be read.
The intention of the iFrame undoubtedly is to increase the amount of interaction on Facebook over shared items. The iFrame certainly makes it easier to comment on the story and re-post the content. What’s interesting is that if you continue navigating throughout the shared site Facebook doesn’t remove the iFrame, instead the iFrame just asks me if I want to return to the original link:

The iFrame is however removed completely if I click on the link or if I navigate to another site from within the iFrame.
By including the Share button Facebook makes it a lot easier to automatically repost stories that appear in my stream. Prior to this change reposting the story would have involved an individual copying the URL, returning to Facebook and posting in the stream, assuming the thought of reposting the story ocurred to the user. Facebook has reduced the number of clicks and pageviews needed to perform this action by more than half and has artfully ‘nudged’ the person into re-sharing the item.
Site owners might object to this change due to the reduction of their screen real estate. But any shortcomings in screen real estate reduction should be offset by the increased exposure that comes from individuals reposting the stories and inreased interaction on the stories. However, the iFrame does steal potential interactions on the site such as commenting with commenting on the Facebook stream. However, I do believe that it’s a net win-win for Facebook and the site owners here.
If there’s any objection to this it might come from Facebook users themselves who may feel inconvenienced by the perceived loss of browser real estate. Remember, there was a backlash along similar lines over the digg bar recently introduced by digg.com. In general, iFrames aren’t very popular and still hold a negative value proposition for many Internet users.
Conclusion: The new Facebook share iFrame is innovative and not too obtrusive. After some initial unfamiliarity I expect that this will indeed increase interaction on shared links and the total amount of link sharing on Facebook.