CNET has been running a special report entitled "Taking Back the Web." The latest dispatch in the 5-part series focuses on mapping "mashups," Web-based applications that are essentially hybrid tools which combine applications like Google Maps with applications such as Craig's List real estate listings (see HousingMaps.Com as a good example.)

While these tools are in their infancy, they're leading the charge to a new wave of innovation in Web 2.0 apps, and providing what I would term "geospatial context" to help find everything from apartments to the best priced gas station in your area. These new apps are, in turn, providing new opportunities for contextual and geo-targeted advertising, a segment of the local advertising market expected to grow to $3.4 billion U.S. by 2009, according to a forecast from The Kelsey Group.