I wonder why productions like Doctor Who don't engage in disinformation to counter spoilers and keep fans guessing. It shouldn't be hard to do, just lie every now and then in an interview, or stage a few "behind-the-scenes" photos intended to be leaked.
"I think the fans will really get behind the new paisley Dalek," Moffat enthused in a recent interview. "Matt thinks they're cool!"
Yeah I wonder this as well. I know when either Life on Mars or Ashes to Ashes was finishing they talked about filling two endings to throw people off but it was BS because apparently they could only afford to film one!
Of course sometimes people just get spoilers plain wrong, I still recall that Harriet Jones was supposed to be inside the Supreme Dalek, and I'm still glad that the identity of who knocked four times was kept really secure.
RTD once said the phone scandles and the thing with the Queen made the BBC very twitchy about them lying to the audience about anything, he said sod it and did it anyway, but the BBC wasn't very happy about it a lot of the time. So that might account for the fact that there's not a lot of disinformation and false spoilers actively put out by the production team.