iPhone 5, iPad 3, Apple TV 3 references found in iOS 5.1 beta
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.
iPad 3 has already been seen in model number 3,1 and 3,2 and now it's joined by 3,3 and a 2,4 (perhaps a Sprint version) as well.
Apple TV 3 is model number 3,1, code-named J33, and again the jump likely represents a processor upgrade, but in this case to the current Apple A5 SoC.
While everyone expects Apple to keep producing iOS devices into 2012, it's still reassuring to see the signs pop up along the way. iPhone 5 could be seen summer/fall 2012, iPad 3 spring 2012, and Apple TV 3... well, that's anyone's guess at this point.