Interestingly, that was exactly what a former intel community official had also complained about when discussing the Snowden case, was when the news leaked of what type of phone OBL was using, that OBL switched to couriers and set back the government in their efforts to track him.

Or in other words, Snowden knew of the national security impact this leak would have and did it anyways. The gracious viewpoint is that he figured the improvement to civil liberties would outweigh the cost to national security. But that still doesn't explain divulging secrets to China, or why Snowden felt that he was unilaterally qualified to assess the risks of each.