Google's capability to "blur faces" on YouTube went relatively unnoticed by the community at large in July 2012. It is synonymous with the blurring of number plates in Google's Street View product. Instructions for using YouTube's video enhancement tool can be found here.

Might it be in preparation for the challenges that may arise from Google Glass?

As citizens continue to play a critical role in supplying news and human rights footage from around the world, YouTube is committed to creating even better tools to help them. According to the international human rights organization WITNESS’ Cameras Everywhere report, “No video-sharing site or hardware manufacturer currently offers users the option to blur faces or protect identity.”
YouTube is excited to be among the first.
Today we're launching face blurring - a new tool that allows you to obscure faces within videos with the click of a button.
Whether you want to share sensitive protest footage without exposing the faces of the activists involved, or share the winning point in your 8-year-old’s basketball game without broadcasting the children’s faces to the world, our face blurring technology is a first step towards providing visual anonymity for video on YouTube.

http://youtube-global.blogspot.com.au/2012/07/face-blurring-when-footage-requires.html

I recently wrote about the use of social media in War. Might the blurring of faces just exacerbate certain limitations? Or is it the right thing to do?

How will we know for certain that evidence has not been manipulated as a result of the blurring? Where will the original recordings be stored? And for how long? Or how might we know if the wrong person is accused of a crime.

During the Vancouver Riots numerous people were caught on "camera" and their face was matched against Facebook and other social media profiles. They became suspects because they "looked" like the perpetrators. People raced to identify them online, despite the wrong identification- in most cases the "identification" was correct, but not in all cases. I spoke about this at the Informa Fraud Conference in Australia in 2011.

YouTube Blog

YouTube Blog