The NTIA has expressed concern to the FCC that LightSquared will cause interference to GPS receivers, degrading or blocking location information for wireless handsets. You can read that letter for yourself by clicking on the link below.
The government agencies concerned about GPS interference are Departments of Defense, Transportation and Homeland Security.
Today, the aviation industry joined in expressing concerns regarding GPS interference. The FCC has posted letters it has received from Hawker Beechcraft Corp., Diamond Aircraft Industries GmbH, and the National Business Aviation Association (a aviation-industry trade group).
This should be interesting!