Changes to how Google’s Quality Score is determined will take effect this week in all advertiser accounts.

There are three main “improvements” to the system; QS is calculated at the time of each search query, keywords will no longer be marked “inactive for search,” and the terminology “first page bid estimates” replaces “minimum bids” in Adwords accounts.

In relation to how Quality Score is calculated, Google will continue to consider clickthrough rate (CTR) of ads and keywords within an account and landing page quality – which is and will be evaluated less frequently.

Quality Score will continue to impact keywords that are inactive for search, but arguably less now than in the past – much less in fact. Google is essentially removing the restriction, rendering all keywords fair game in a PPC campaign. Although Quality Score will continue to impact how often (frequency of impressions) keywords are shown, this will change. Some keywords marked "inactive" may perform very well for certain queries in certain circumstances and, as such, may begin to receive impressions.

The inclusion of first page bid estimates and the removal of the “minimum bid” wording within Adwords accounts is more than just a cosmetic enhancement to the platform. First page bid estimates should be close to your existing minimum bid according to Google, but queries with a high level of advertiser competition may have significantly higher first page bid estimates. The result? Advertisers will need to bid above the old minimum to rank higher than the competition and show on the first page.