Futurcasting, how does O’Reilly do it:

Our methodology is simple: we draw from the wisdom of the alpha geeks in our midst, paying attention to what’s interesting to them, amplifying these weak signals, and seeing where they fit into the innovation ecology. Add to that the original research conducted by the O’Reilly Research group, and you start to get a good picture of what the technology world is thinking about. What books are people just now starting to buy, and which are falling off in interest? Which tech-related Google AdWords are rising or falling in price? What can we learn from predictive markets tracking tech trends? Which open source contributors look to be on the track of an interesting project — or set of projects?