A couple savvy advertisers posted in WebmasterWorld that they noticed major changes to their quality score metrics for a nice number of keywords in mid-October, specifically around October 14th or 15th.
The first advertiser wrote:
I do have the feeling that something happened with the Quality Score around October 14-15 (give or take).I have many accounts I handle, and a lot of them got their Quality Score changed ( downwards of course, I wouldn't complain on the other way happy! ).
Another advertiser said he saw a similar thing, saying, "I hate to say it, but I noticed something similar as well."
Did you notice anything?
Forum discussion at WebmasterWorld.