During WWDC 2013, Apple announced the completely redesigned iOS 7 and the beta will be available on the iPhone to developers beginning today. The beta for iPad will be available in the coming weeks. For the rest of us, we must wait until fall for the official release.
iOS 7 will be available on the iPhone 4, iPhone 4S, iPhone 5, iPad 2, iPad 3, iPad 4, iPad mini, and 5th generation iPod touch.
Fall can't come soon enough!