Data from services like Google Maps or Foursquare cannot be used for marketing or communication. For example, Google Maps Terms of Services (3.2.4) say "Customer will not extract, export, scrape, or cache Google Maps Content for use outside the Services".

Data from The Data Pond are under the Open Data Commons Open Database License (ODbL).

"You are free to copy, distribute, transmit and adapt our data, as long as you credit OpenStreetMap and its contributors. If you alter or build upon our data, you may distribute the result only under the same licence. The full legal code explains your rights and responsibilities."

The data you will get from The Data Pond are not as rich as data from services like Google Maps or Foursquare but, at least, it is legal to use them.