There's a lot of information a map can provide. Just taking a look at what Google Maps already provides is testament to that. There is one area, however, that most maps don't make use of - demographics.
That's to be a thing of the past since Google has announced that their Maps API for Business is now getting a U.S. Demographic Layer. This will allow developers to launch new map applications that feature demographics information.
All the demographic data used in the new feature comes from Nielsen. The information you can expect to have access to includes population, age, race, marital status and housing status. The data available is from 2010 and 2011 alongside projected data for 2015 and 2016.
As for actual use of the Demographic Layer, developers can "control how the data is styled, such as defining color thresholds or gradients, and also define style rules based on expressions across statistics that are evaluated in real time." Google uses the example of using color to visualize population density on the map.
You can start using the Demographics Layer now if you're inclined to. Just be aware that you can only use it for internal applications. For an idea of how to use the new layer, check out the documentation here. It should give you all the information you need to get started on making new applications powered by demographics data.
Here's a video that explains all the features of the Demographics Layer. It also gives you an idea of how you will be using the layer. Check it out and tell us what you think: