This may mark the starting of ‘an end of a great era’. AT&T officially announced that they will be shutting down the dated but still the most popular 2nd generation network, the GSM, in the US in coming five years. Perhaps this was imminent with the advent of mobile broadband technologies and VoIP, but what a journey it has been, 20 years!
Now I am not sure if AT&T is the first operator to announce such a transition but more operators are likely to follow the same course to free up that juicy spectrum for upcoming 4G systems. Its just a matter of time.
You can read more on this and how AT&T is planning to cope with the customers having 2G only handsets. Link