Re: A thought on regenerations (spoilers for "Night/Day of the Doctor" All of that was utterly obliterated in the 50th Anniversary special. Again, we saw Capaldi was the 13th Doctor. He was acknowledged as the 13th Doctor. It wasn't "All twelve-plus-a-guy-spawned-from-a-hand incarnations plus, uh, some other dude!" It was "All thirteen!" Followed by a tease of Capaldi's eyes, not a second Tennant's. That's actual canon. As opposed to something Moffat's flippantly thrown out there in order to mislead people so he can "surprise" us in the upcoming special, ala JJ Abrams. That said, I'm sure there'll be some wonky stuff going on as it wouldn't be Doctor Who if there wasn't. I also have little doubt that Smith's Doctor won't come to the same conclusion that Moffat is suggesting either (in fact, it's all but certain he will based on the trailer). But that doesn't change the fact that we know in both the real world and within the show that Capaldi is the 13th incarnation of the Doctor. Hell, at no point has Tennant showed up twice in the myriad times they've shown all the Doctor's incarnations, certainly not the times they've shown all thirteen.