Now this one has some credence. The idyllic, lush greens of the nethersphere gardens along with the whitewash walls of its interior have led some to believe that heaven is the Library databanks from series four in which Rivers consciousness is saved. This being a computer, River could easily be given a new face (Photoshop, anybody?) which wouldnt cause continuity errors as River gave the Doctor her unused regenerations in series six. Ultimately heaven acts exactly how the databanks do; some form of consciousness of a recently deceased person is saved somehow and is allowed to live forever after in heaven (despite being technically dead). Perhaps River is simply trying to populate the Library databanks (which, after all, only housed four or five people after everybody was saved). As River lamented, everybody lives. This theory could tie into that of Missy being the TARDIS, with the Doctors guilt somehow saving those he has killed. But like weve said, we doubt the Moff would create a good story arc, and nobody bar Alex Kingston can play River Song. She is exceptional. This theory is possible, but probably isn't correct.
