Roadmapping is the practice of creating time-based representations of information designed to support a specific objective or decision process. When used as part of a strategic planning operation, roadmapping can foster innovation by forecasting the elements needed to address future technological needs or market demands. 
One famous example is the International Technology Roadmap for Semiconductors. Several large semiconductor companies get together yearly, and talk about where they think technology is going, what kinds of blocks are in the way, check who's working on different problems, and make sure that there are people addressing problems. They are strategy stessions for getting to the future.
An example of a small roadmap is "Escaping the Java Trap: A practical road map to the Free Software and Open Source alternatives." Look at it, and you'll see the status of where things are, projections of where things will be, specific notes on who is working on what, and notes on what the goals are, and notes on strategy for getting there.
- Roadmapping resources at Strateva