Given my experience with embedded systems, to be honest I'd be shocked if anyone's CPU died, even after a year locked 100% load at 1ghz. 50C just isn't that hot.

The spec sheet publishes the worst-case-scenario.. theoretical minimums/maximums. But frankly, I bet the things to fail in our phones will be the switch-mode power supply, offchip capacitors, radios, etc... long before a 1ghz OC'd CPU.