Still in the IHT, an interesting account of how map web services emerged ans how they will evolve:

In 1991, David Gelernter, a computer scientist at Yale University, proposed using software to create a computer simulation of the physical world, making it possible to map everything from traffic flow and building layouts to sales and currency data on a computer screen. Gelernter's idea came a step closer to reality in the past few weeks when both Google and Yahoo published documentation making it significantly easier for programmers to link virtually any kind of Internet data to Web-based maps and, in Google's case, satellite imagery.

Since the Google and Yahoo tools were released, their uses have been demonstrated in dozens of ways by hobbyists and companies, including an annotated map guide to the California wineries and restaurants that appeared in the movie ''Sideways'' and instant maps showing the locations of the recent bombing attacks in London. Later in the summer, Microsoft plans to introduce a competing service, Virtual Earth, with software that will enable programmers to use it in similarly creative ways.

So far, the uses have been noncommercial. But Yahoo, Google and Microsoft are creating the services in the expectation that they will become a focal point in one of the next significant growth areas in Internet advertising: contextual advertisements tied to specific locations. Such ads would be embedded into maps generated by a search query or run alongside them. (...) ''In the past there was a grain-silo approach to controlling the technology,'' said Nathan Torkington, director of Where 2.0, a location technology and mapping conference held last month in San Francisco. ''Now we're seeing the distribution of mapping technology.''

Why do I blog this? even though I don't like the "contextual advertisements tied to specific locations" thing, it's definitely true, mapping services is a both a top-down (availability of technologies thanks to big companies) and bottom-up (map hackers developed applications) phenomenon. Which is an interesting innovation model.