On November 30, 2010 the US Air Force announced plans to upgrade the GPS ground system with a new software release in early December 2010.
You can read the US Air Force press release at http://navcen.uscg.gov/pdf/gps/GPS_Software_Upgrade_Release.pdf.
Notice Advisory to NAVSTAR Users (NANU) 2010144 announced that the ground segment software upgrade would be installed on December 1, 2010.
You can read NANU 2010144 at
http://navcen.uscg.gov/?pageName=selectNanuByNumber by selecting 2010144 under either the GPS NANU Number or the GPS General NANU Number selection option.
The GPS ground system software upgrade was tested prior to installation and should be transparent to GPS users.
Any GPS user experiencing a problem should report their problem to the US Coast Guard Navigation Center by the internet at http://navcen.uscg.gov/?pageName=gpsUserInput or by phone at 703-313-5900.