An odd bug has developed this morning. At the moment, api.stackoverflow.com/1.0/questions is returning a question of the format...

        ... },
        {
          "tags": [
            "jsf-2.0"
          ],
          "answer_count": 1,
          "favorite_count": 0,
          "question_timeline_url": "/questions/3907189/timeline",
          "question_comments_url": "/questions/3907189/comments",
          "question_answers_url": "/questions/3907189/answers",
          "question_id": 3907189,
          "owner": {
            "user_id": 463053,
            "user_type": "registered",
            "reputation": 6,
            "email_hash": "74a43b5cb5829f78b4a4be155c8d702c"
          },
          "creation_date": 1286807749,
          "last_edit_date": 1286810790,
          "last_activity_date": 1286811106,
          "up_vote_count": 0,
          "down_vote_count": 0,
          "view_count": 4,
          "score": 0,
          "community_owned": false,
          "title": "jsf 2 project structure"
        },
        { ...

Note that the `owner` sub-object has no `display_name` key (`display_name` is non-optional according to the documentation). The single question route, http://api.stackoverflow.com/1.0/questions/3907189, returns the `display_name` as "user463053".

This has broken Six to Eight, as the response decoder now fails with a missing mandatory key error.