Hello. There is something I've been curious about since I first discovered the Avatar Wiki.
Exactly how involved have Bryke and the various other writers, etc. of Avatar: the Last Airbender and The Legend of Korra been with this Wiki? Do they contribute or otherwise give their input on info, history, etc. from the shows and comics?
They are largely uninvolved. The information found here is written by fans based on the information gotten from official sources, like the episodes, comics, graphic novels, and the nick.com site. There have been rare occurrences where the creators have answered questions, but they have never edited for themselves.
There has been someone of the crew who requested a different picture of them to be up on their page (I can't remember who it was though, sorry), but other than that, I don't think they edited. There was a Q/A once here on the forums, though.