Whether or not you buy into T-Mobile CEO John Legeres UnCarrier strategy, we cant dispute the fact that its at least making waves in the US wireless industry. Some of the networks biggest competitors are responding with new strategies of their own, and ATT is one of them. Starting next Sunday, the GSM giant will make a few noticeable tweaks to its Mobile Share and Next plans. Whats on the menu for December 8th? Quite a bit, so lets break it down.