Originally Posted by Simon_Foston:
“The Doctor Who "canon" consists of the TV series and nothing else, because there is no widespread consensus as to what else should be in it. The word "canon" implies universal agreement, which is why I consider the idea of a "personal canon" to be nonsensical. I'm hardly likely to disagree with myself about what Doctor Who consists of and what it doesn't. My opinion, though, is that if a character, setting or storyline forms a significant part of a TV serial, and isn't just fleetingly referred to as in the case of the 8th Doctor's BF companions in The Night of the Doctor, then he, she or it can be considered "canon." I suspect that the TV writers will never use anything from books, comics or audios in any significant way, so they'll never be canon.”
I think, as you say, personal canon is a bit irrelevant but, IMO, the important thing when talking about Canon is what the current production team consider Canon. It determines whether we can legitimately complain about them breaking continuity or not, which is, of course, vital to any Doctor Who fan
It can also be useful to know because sometimes the TV show may drop clues or hints about certain unresolved mysteries and if these hints might be affected by other things (such, as whether the Doctor is half-human, for example) we would better be able to draw valid conclusions from those hints if we knew whether these things, as raised in other forms of media, were Canon or not.
Now it seems pretty certain that the TV Movie is Canon because Paul McGann as the 8th Doctor is Canon so, personally, I consider the half-human thing to be Canon even though I expect it to be too much of a hot potato to ever be explicitly referenced.
I don't think the audios are Canon as such, only because I don't expect the production team to have an encylopedic knowledge of their continuity or want to shackle themselves too heavily in an attempt to conform to it but I suspect that a lot of the team are fond of the audios and have no particular agenda to contradict them.