The wireless industry has agreed to notify cellphone users when they are about to ring up extra charges after reaching their plan's monthly limit or using international roaming minutes outside their plan, the Federal Communications Commission announced this week. FCC Chairman Julius Genachowski said the warnings will reduce the prevalence of "bill shock," an industry term for when subscribers experience a sudden, unexpected increase in their monthly bill. One woman received a $34,000 monthly bill after visiting her sister in Haiti in 2009, Genachowski said. The alerts will be sent to subscribers by voice or text message. Genachowski said that carriers have agreed to implement the notification system as quickly as possible. Read Chairman Genachowski's statement here.