9to5Mac has found some code references in the recently released-to-developers iOS 5.1 beta for iPhone 5 (or whatever Apple ends up calling it), iPad 3, and Apple TV 3.
The next iPhone is model number 5,1, representing another large internal upgrade, likely a next-generation Apple A6 system-on-a-chip. (iPhone 3G was 1,2, iPhone 4S was 4,1, so factor that into your tea-leaf reading about Apple's 2012 naming conventions.
