This is the next step for Google to take. If another company manages get this service out for free first, they will be the new search engine everyone goes to. This alone could be highly profitable if they aren't as reluctant to use ads as Google is.
There's been a big back-and-forth about how big an impact QA can make on information-retrieval. A few points:
Writing a proper natural language question isn't necessarily easier than writing a Google query. You don't always know what you need to know, and providing feedback from the QA system is very difficult. You can iterate towards the right query fairly well, as your searching teaches you better keywords.
The percentage of queries that can be answered by a single sentence is substantial, but might be smaller than you think. People also use search eng
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