Canon and non-canon scenes?

[Ashen Key]

My thoughts are very simple - the original theatrical release?

Canon.

Everything else?

Optional canon, to be used or not used as the fan sees fit. (And this is not just in Avatar fandom, but other fandoms I'm in and have been in).

Which means in my own canon? Absolutely are Trudy and Norm shagging, and of course Neytiri had an older sister...but that comment about the Na'vi not knowing how to lie? That I ignore, because it makes little sense and has unfortunate implications and I personally dislike it. And it was in a deleted scene, so Cameron didn't rate it important enough to include. So, yeah. Basically, original theatrical release? Canon. Everything else? Semi-canon, optional canon, can-be-ignored canon.