Canon, schmanon. Who cares? JJ Abrahms certainly doesn't. Or else he would not have Kirk, Spock, Bones, Uhura, Sulu, Scotty, and Chekov serving on the Enterprise at the same time!?! And one of the craziest things about that situation is, even though Chekov is about 12 years younger than Kirk, he apparently outranks him on the bridge of the E (Chekov is wearing a gold command uniform while Kirk is still in the black cadet garb). That in itself is contradictory since Kirk is Captain of the Enterprise in TOS and Chekov is an Ensign in Season 2 when he is introduced.
Okay. To me, canon is TOS. Everything in TOS. Timeframes, character ages, anything that stayed consistent for more than one episode should be considered canon. I'm very irritated with this new movie and all it's canon violations. And I don't know if I will like it or not. But because it is Star Trek. I will watch it.