On Wiki it states that Christopher Eccleston is the ninth doctor :/ so how could John Hurt be it?

Well we never saw McGann regenerate into Eccleston, so it's plausible that another incarnation could have existed during the time war but that he didn't go by the name Doctor.

we don't actually know yet where or how he fits, and nor should we, it's what the 50th will be about, would not be much of a story if you knew now, would it? Patients!

Because the incarnation that was John Hurt did not use the name The Doctor so does not count in the sequence?

Because they hadn't thought about making a new 9th Doctor until this storyline.

If Hurt is confirmed to be the real 9th in the 50th anniversary then Wiki and all other websites will be updated to show that

Hurt will be 9
Eccleston 10
Tennant 11
Smith 12

And obviously wiki is the best source out there. We're not sure, but its been all but confirmed really.

Well he clearly doesn't, as we've never heard of him before. If he is indeed the ninth incarnation then that's what we'll call him - the ninth incarnation. The Ninth Doctor will be the tenth incarnation, the Tenth Doctor the eleventh incarnation and the Eleventh Doctor the twelfth incarnation, but they will retain their numbering as The Doctor.

He's the 9th incarnation, but not called the doctor, that's why Eccleston is. If the rumours are true that is.

However onscreen the titles said "Introducing John Hurt as The Doctor".....

That was just done for dramatic effect I assume. That and now he's revealed, he will just be called The Forgotten Doctor, or something like that.

I think some are overly concerned with the numbering when we don't know yet what the status of JH's character is yet. He may not be a true incarnation. Maybe he is a dark side that runs simultaneously to 8. Maybe he is a Valeyard type character that exists "between" incarnations. There doesn't appear to be any substantive evidence that there is going to be any re-numbering of the Doctors.