SMS emergency alerts?

Sounds like they're a long way away from actually implementing anything, but the Senate Subcommittee on Disaster Prevention and Prediction has been talking about expanding the Emergency Alert System beyond televisions and radios so that they can use SMS to automatically notify cellphone users about disasters or terror attacks. It's not clear whether the system would be mandatory or not, but the Federal Emergency Management Agency is about to start testing a new Geo-Targeted Alerting System that would provide warnings only to potentially affected households and businesses (rather than just blasting warnings out to everyone), and as part of that they are considering an opt-in system that would let you pick and choose how you want to be contacted.