Since the last wipe and big update I've seen many players on the forum, often new ones, taking information from the wiki as valid and created and leveled characters based on that information which later turned out completely wasted time and effort as the aimed perks or proffessions have changed requirements or don't exist anymore. This demotivates people, especially new players just starting.
My Suggestion: Put a big banner on the wiki saying that some pages regarding crafting professions and perks are currently outdated and a link to the threads the devs made with the information about the new features (primary and secondary perks, proffessions etc)
Or: Do the foolproof way and replace the wiki by that banner completly and do a tiny link "to the old, outdated wiki" at the bottom.
TL;DR: We had many posts about "why don't I get perk x, i have x% skill? It says that on the wiki!" only to be answered with "doesn't exist anymore, wiki is outdated" - Mark wiki as outdated on frontpage of wiki or replace wiki with a reminder that is outdated completly with link to old wiki.