Facebook is a great resource to find out about friends graduating, getting married, and going on vacation. Apparently it's also a good resource for Taliban fighters to spy on soldiers.
According to Australia's Department of Defense's new report on social media (PDF), "the Taliban have used pictures of attractive women as the front of their Facebook profiles and have befriended soldiers" as a way to gather information.
These fake profiles are a cause for concern, notes the report. The goal of the report is to be a training guide and review for Australia's military in teaching its soldiers how and when to use social media.
When the U.S. military in Afghanistan created a Facebook page in 2009, it's primary objective was to counter Taliban propaganda, which supposedly often publicized false claims about soldiers and civilians killed in the war. It's unclear if this Facebook page was ever then used a resource by the Taliban.