Steven Johnson points to an article in PhySorg: "What they found were some general correlations of size and resource consumption that more or less fit the biological organism metaphor, meaning as the city grew in size it required less energy (resources) to sustain it in a proportion called sublinear scaling. What was surprising to the team was when they measured creative output (jobs, wealth generated, innovation) as cities grew, the scaling of this output was not sublinear, but superlinear, meaning as the city grew its creative output grew faster and faster."

WSJ has a commentary by James Stewart about Google: "It's becoming apparent that Internet advertising, in its myriad permutations, isn't just a new variation on traditional advertising. The ability of online advertisers to place information in highly targeted contexts in which users can click through to further information and even make purchases seems so revolutionary that it can hardly be called advertising at all. It may well be that the frequency of ad usage will generate the same data-intensive refinements that exist in the search field, yielding similar economies of scale -- and a natural monopoly."

InformationWeek has a nice way (from Google) to describe mobile usage:

Google breaks down mobile users into three behavior groups:

A. "Repetitive now"
B. "Bored now"
C. "Urgent now"

The "repetitive now" user is someone checking for the same piece of information over and over again, like checking the same stock quotes or weather. Google uses cookies to help cater to mobile users who check and recheck the same data points.

The "bored now" are users who have time on their hands. People on trains or waiting in airports or sitting in cafes. Mobile users in this behavior group look a lot more like casual Web surfers, but mobile phones don't offer the robust user input of a desktop, so the applications have to be tailored.

The "urgent now" is a request to find something specific fast, like the location of a bakery or directions to the airport. Since a lot of these questions are location-aware, Google tries to build location into the mobile versions of these queries.