And I started searching if there is anything new from Google and found that Google sent seroundtable a statement confirming a test. Google said:
We are currently running a limited test in which a small number of users are seeing ads that are marked based on signals related to quality and relevance. This experiment is part of our ongoing efforts to help users find what they're looking for, and we're closely monitoring feedback.
Initially my thought was that it has something to do with Ad Targeting feature where some advertisers are targeting my channel but after investigating on Go4Expert.com I saw that the advertisers targeting Go4Expert.com Channel don't have such stars.
Second experiment on browser with cleared cache's and cookies does not have such yellow star ads which means Featured ads are shown only when Google have enough data about user's interest.
What Kind of Featured Ads you see ?