(Updated with statement on tethering) AT&T this afternoon finally established a firm date for when it would add MMS support to iPhones on its network. The carrier will switch on the feature as of September 25th through a software upgrade for iPhone 3G and 3GS owners. Adding the feature will let those running iPhone 3.0 or later firmware send photos, videos and general data like contact cards to any MMS-aware phone.
