Building a centralized database to process billions of open-ended queries per day is a mammoth undertaking. It appears that Google, who perhaps is the only company on the planet with enough imagination, incentive, and expertise to effectively build such a
H. Chen, F. Perich, D. Chakraborty, T. Finin, und A. Joshi. Proceedings of the Third International Joint Conference on Autonomous Agents and Multiagent Systems - Volume 2, Seite 854--861. Washington, DC, USA, IEEE Computer Society, (2004)