So many great new devices, promos, and data plans are being announced. The more mobile technology is improving, the greater network coverage, the faster connection, and the better data plan deals will be. AT&T is always quick to upgrade its systems and plans. Just last month, it started offering unlimited calling in Mexico and rollover data plans for shared subscribers. AT&T isn't the only carrier offering new plans though. Verizon was earlier tipped to slash $10 off most data plans last week. AT&T's prepaid carrier has also unveiled a new All-in Prepaid Plan while Verizon announced more data plan options for prepaid subscribers.