On June 21, 2016 the FAA released much awaited Part 107 regulations detailing commercial drone use; the regulations will likely become effective in August 2016.
These new regulations provide guidance for routine commercial use of small unmanned aircraft systems (summary).
Part 107 will not apply to model aircraft. Model aircraft operators must continue to satisfy all the criteria specified in Section 336 of Public Law 112-95 (PDF) (which will now be codified in Part 101), including the stipulation they be operated only for hobby or recreational purposes.