At SMX West last week, Google's Paul Haahr, a top engineer involved in core ranking, had a keynote Q&A with Danny Sullivan. He said many interesting things including that Google doesn't fully quiet understand RankBrain.
Here are two tweets from the session, which I sat in:
As you know, RankBrain is Google's query interpretation that uses artificial intelligence. It has been live in Google for very large fraction of queries since earlier in 2015. Now, Amit Singhal retires and he is replaced by the head of RankBrain at Google. So it seems RankBrain will power more and more of search.
What does that mean? It is hard to explain according to Paul Haahr of Google. He wasn't able to tell us more than we know but he joked on some level that even Googlers doesn't know what it means exactly.
Scary - no?
Forum discussion at Twitter.