Google Adwords has made some changes to the way they calculate Quality Score – it’s now being done in real time. Quite how this is possible is a mystery so far, I’m sure Google isn’t able to load every website and test the landing page in the 0.05 seconds a query takes to execute so they can’t be testing landing pages in real time.
The real time factors are likely to be CTR, ads and keyword relevance rather than on-site factors, with on-site factors updating Quality Score periodically.
we are replacing our static per-keyword Quality Scores with a system that will evaluate an ad’s quality each time it matches a search query. This way, AdWords will use the most accurate, specific, and up-to-date performance information when determining whether an ad should be displayed. Your ads will be more likely to show when they’re relevant and less likely to show when they’re not. This means that Google users are apt to see better ads while you, as an advertiser, should receive leads which are more highly qualified.
The main impact of this is that keywords with a low quality score won’t be marked “Inactive for search”, in effect they will still be inactive for search but you just won’t know about it until you look at the stats and see that they didn’t accumulate any clicks, so this shouldn’t impact the way an Adwords campaign is run.