"These are tales told around the campfire, " said one U.S. official, adding the information is "interesting" but hardly points conclusively to any action.

CNN: Sources: American Taliban fighter says new attack planned on U.S.

One challenge for Quora will likely come in maintaining its campfire-circle quality as the site grows beyond its current core audience.

FORBES: Quora: A Technology Writer's Best Friend, For Now

One, a woman, transfixes two others with what she is saying across a dying campfire.

NEWYORKER: Flashes of Light