The FAA adopts IMHO a more enlightened and more reasonable approach to flying single-engine helicopters over congested areas.
Extract from
FAR Sec. 91.119 - Minimum safe altitudes: General
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface.
(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.
(c)
(d) Helicopters. Helicopters may be operated at less than the minimums prescribed in paragraph (b) or (c) of this section if the operation is conducted without hazard to persons or property on the surface.
In addition, each person operating a helicopter shall comply with any routes or altitudes specifically prescribed for helicopters by the Administrator.
(In addition, there are provisions equivalent to the ANO relating to endangering the aircraft and people/property on the ground.)
Over Los Angeles 1997 - a week's break from the law. 
FL