Starting today, we will be updating how we report 1-10 Quality Scores for keywords [https://goo.gl/c4Oi7
]. This update only affects reporting. There is no change to ad serving such as how auction-time quality signals affect Ad Rank and CPC. The most significant part of the change is that keywords without traffic will now, by default, receive a score of 6, and Average for the three components of Quality Score. Once keywords gather enough impressions, scores will update about a day or so later.
Behind the scenes, this change will allow us to simplify some of our core systems, letting us focus our attention on improving reporting accuracy for keywords with traffic.