Originally Posted by
GDK:
“A regeneration or resurrection (especially like the Master's returns)? No. Just... no.
I can't quite bring myself to believe it'll be just at some random point in River's timeline. It has to be about some special event that couldn't possibly be told without River (and, possibly, her ultimate fate) being an important part of the story.
I think we can pretty much rule out 12 taking River to the singing towers because 11 heading there with her has already been shown (and yes, I do believe the mini-sodes are canon, given that they were made at the same time as the broadcast series and the writer and the production team that made them are also the people who made the broadcast series. There's really no reason to treat then separately from the main series). In-verse, I think it's highly unlikely that they would repeat that given the characters of both River and the Doctor. In the real world there'd have to be a really good story to be told that requires that event to be shown to make it worth a revisit. And SM would have to be convinced of that.
Therefore, I'm going with the fourth option. 
”
I disagree. Not about the minisodes being canon, I'm fine with that, but What I disagree with is the fact that you conclude that it is ruled out based on a few lines in one of them. All we know from the minisode you are thinking of is that as far as River was concerned, the doctor was going to take her there. Now for one thing, the doctor so very often gets diverted from planned locations by either his own choosing or that of the TARDIS that an original plan for them to go there is no evidence in the doctors world that they actually did. Another option -the doctor lies. River remarked that he had 'been promising me for ages' so if the doctor had wanted to get her somewhere, perhaps somewhere she didn't want to go, then maybe that's how he'd do it, by saying they were going somewhere he knew she really wanted to go. Thirdly, as I've mentioned before - who say's they didn't go more than once?. It could easily be that when the doctor takes her there for their final day, that he is doing so because it is a place they have fond memories of together from a previous visit.
Now, If your still reading at this point, I suspect you might be thinking 'ah, but the future doctor gave the earlier doctor a sad look, that proves it' but again, it proves nothing. If we take the idea of the doctor lie's and couple it with the fact that future doctor's don't really like to give away much to an earlier incarnation, it's easily plausible that the future doctor knew that the present one would be sad and worried on hearing derillium, and rather than be revealing, just went along with what he knew the past doctor might expect. Or it could just be a mutual sadness knowing that one day the derillium trip would be his and her's last, so feeling sad about that fact but knowing that it wasn't going to happen that day.
The point is - yes, if we never see River and the doctor at derillium together on screen, then you
could just assume that the minisode was showing her final trip and that it was with 11, but at the same time, any which way I look at it, there is nothing concrete to prove that the final derillium trip was with 11, and to show it with 12 would be perfectly fine.
I don't know if it will be in the christmas special, or ever on screen at all, but for me, for Moffat to start her story with such a powerful description of the end of it, and never actually show that end, would seem like a huge wasted oppourtunity.
If this is her last episode then I'd love to see it, but if Moffat is envisioning river with 12 further down the line in more episodes then maybe christmas should just be a 'random point in her timeline' (but pre death of course, no data ghost rubbish or undoing). As such I'm a bit torn with the poll options.
