Was Donna meant to die in the Stolen Earth/The Journey End? There were several cases of foreshadowing her death, and Dalek Cann explicitly said "One will die". She could easily have died from brain overclocking, and she was written out of the show (ok, wiki tells me she shows up for a cameo later, but that was probably not planned this far in advance). Yet, she lived. No companions of the 9th or 10th doctor actually died, either; I was thinking we were probably due for an important character death. Was this executive meddling or a last-minute decision? Or was it always meant to be a metaphorical "death"?
In other words, was there at some point plans to kill off Donna entirely that got changed into the current scenario instead?