Lyddiegal, please follow suit and use white text out of courtesy as the rest of us do please! 🙂
Anyway, I like your line of thinking DHUK, perhaps Donna does still have something on her back and will need to change the past, possibly by sacrificing herself as she did in "Turn Left". The question is though, how did she get another "time beetle" on her back, and what decision does she need to make to somehow change what happened?
And then how much of it changes? The entire episode (that would suck, as it would be akin to "it was all a dream!" and never happened) or just the single event of the Doctor being shot? Hmm, and knowing that the Doctor isn't dying, rather simply regenerating, would Donna think this is worth sacrificing herself for? In a way, what bearing does it really have if the Doctor continues in his 10th form or in his 11th? Apart from the standard recovery time, he's the same Doctor and would have the same success in defeating Davros one way or the other.
Regardless, even if Donna does make some change to avert the Doctor's regeneration, it will still be interesting to see what becomes of the Doctor in the interim. 😉