In a single word, managing context in a world of changing expectations, was the key concept in this morning's Facebook privacy briefing. The company is listening. Both to what you are saying - and what you are doing. We listen to the net promoter score and find out if you promote Facebook to your friends. In Mark Zuckerberg's presentation and Q&A this morning, it is easy to see how hard it is to gain a common context for the problem of global solution of how we view sharing.