Currently the US government forbids commercial use of drones to collect aerial imagery. The FAA is supposedly reviewing this to determine what sorts of restrictions are needed to allow this to happen while minimizing threats to privacy. From the Denver Post:
Last year, Congress mandated that the Federal Aviation Administration create a plan for the safe integration of unmanned aerial vehicles into the national airspace. Those regulations should be complete by 2015, and the agency expects a commercial boom — as many as 30,000 drones airborne in the U.S. by 2020. But public fears about police spying could stall the technologically advanced industry eager to be unleashed.
What countries currently allow commercial use of drones to collect aerial imagery?
In these countries, have there been problems with invasion of privacy?
Update
The influential head of Google, Eric Schmidt, has called for civilian drone technology to be regulated, warning about privacy and security concerns. - BBC News