tedster - 6:00 pm on Dec 29, 2011 (gmt 0)
there is no way their computer can compare all the sites for every search in the world almost twice a day.
Google uses over one million computers, very cleverly networked into big server farms. In fact, most of Google's programming can't even RUN on a single computer.
If you go back and refresh your understanding of the "Caffeine" infrastructure, it might clarify things a bit more.