On Monday, Google announced that they will be changing how they report keyword quality scores in AdWords, effective immediately. Before you panic, the changes are only going to affect the numbers you’ll see in AdWords, not the way quality score is calculated or the ad auction.
Google explains the reason for the update:
“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.”
The most obvious (aka, the most visible) change to the reporting is before receiving traffic, keywords are now going to default to a reported score of 6. Scores are going to update when enough impressions accumulate in a day or so.