Why Google pessimists may be mistaken

"If we are right and it takes 5-6 years for search to mature globally (instead of 2 or 3 years)"

Hard for me to believe that search will 'mature' in even 6 years. Seems to me like there are at least 10 years of work and market expansion to do to address interaction (e.g. voices, gestures), personalization, socialization, and access points (e.g. cars).