What's next for Search?
IMO it is foolish to think something can replace Google search for web search. But it is not imprudent to think about what will replace the text-based search. For a long time, IBM remained the champion for mainframes but mainframes got replaced by PC and not IBM in mainframes. Everyone knows what happened to Kodak or Nokia; change is inevitable.
The form factor keeps on changing and it is very wise to think the text-based search market will shrink. The future, in my opinion, is voice search and the competition for Google are voice assistants like Alexa, Siri, and Google AI itself. The search is becoming more and more contextual and you will start receiving most of your info from the voice assistants themselves. Recommend a movie, what's the news, buy a pair of socks, etc. Google will remain important for broad-based topics and research but the market will move! If you look at top searches, you don't actually need Google websearch for that like results, weather, people, etc. Other mediums have become mature enough to serve the demand with a better experience too.
This will also change the ad monetisation strategy. The advantages Amazon here are unparallel as it also owns the e-commerce/ selection part of it. But it is also too early to predict who will emerge as winner or is it an oligopoly play with each one having its own point of differentiation. Let's see!