Has the FAA banned FPV for model aviation?
The FAA has interpreted the rules to mean that the operator must have a line-of-sight view of the model aircraft at all times, and that FPV does not qualify.


  Based on the plain language of the statute, the FAA interprets this
  requirement to mean that: (1) the aircraft must be visible at all
  times to the operator; (2) that the operator must use his or her own
  natural vision (which includes vision corrected by standard eyeglasses
  or contact lenses) to observe the aircraft; and (3) people other than
  the operator may not be used in lieu of the operator for maintaining
  visual line of sight.


But also note that this does not apply if:


  ...the aircraft is operated in accordance with a community-based set of
  safety guidelines and within the programming of a nationwide
  community-based organization;


The above is from the linked NPRM released in June 2014. The latest NPRM from February 2015 has the same requirements.

So members of an organization like AMA are exempt from that rule. The AMA requires a spotter to be used when flying FPV.