The firm said that that there's a one in five chance that the constellation will drop below the minimum 24 satellites needed to cover the globe at various times between 2011 and 2012
This says there's a 20% chance that we will have less than 24 active satellites in 3 years time. That doesn't mean GPS will cease to work entirely. This just means some spots on the globe may experience reduced accuracy due to a lack of visible satellites. The point of this article is that the Air Force is not taking the proper steps to ensure they are replaced as fast as they might start dying.
TomToms and cell phones aside, most applications that really need to know where they are have multiple backups, and the world won't stop running just because GPS is a little less accurate. Commercial planes, for example, primarily use INS (inertial navigation), GPS is a backup. They also have plenty of navigation radios like VOR, TACAN, DME, etc...