Following the pilots, implementations are expected to be more widely available in final form throughout 2013 on mobile handsets.

Facebook, whose offer consisted of $300m in cash and 23 million of its shares, has lost some of its luster since its May flotation.

Delegates have the unique opportunity to meet with elected officials at the national, regional and local levels, as well as policy makers.

China's economy grew 7.6 percent in the second quarter of this year, its slowest pace in more than three years.

The group replaced the website's original content with a statement that called on the team to "immediately apologize."

NASA has named the site "Bradbury Landing," a nod to the late science fiction author and space aficionado Ray Bradbury.