The latest news about Google's head of search, Amit Singhal, to leave the company he spent 15 years with, had the shocking effect on the SEO community. And what is more surprising - his successor, John Giannandrea, is the one who has worked on artificial intelligence at Google (including RankBrain - the part of search algorithm which uses AI to work with a queries search engine was not able to understand before). With this change of executives, we may be on the verge of a new era - the era o...