Read moreGW2 is all about being dynamic. Dynamic events, vendors, etc., however I feel that the wiki is much less so and we (the community) probably have mostly ourselves to blame. The wiki and community are still young and I believe that both will be more well-rounded in the coming months. Currently, however, the amount of relevant content is lacking.
For example, my most recent encounter was with the vendor of Bauble Bubbles. The wiki still indicates that they can be turned into the merchant from the event in Rata Sum for various items, and although the vendor is still there, he no longer offers items in exchange for the Baubles. His own page on the wiki also makes no mention of the fact that his services are no longer available.
I'm just as guilty as anybody for not rectifying these things (such as the above), but if we want the wiki to be a good source of truth for the game, they need to move in sync. I think community awareness posts such as this one are a great start....
There's actually a good example of that on the wiki and I thought that I'd mention it. This was coded by one of the wiki editors (I believe he's on this reddit thread too :) ) recently on the wiki, after we released the API: take a look any article about a dynamic event (for example: http://wiki.guildwars2.com/wiki/Capture_Stonecrag_Kraal), then on the right you'll see the infobox and at its bottom the title "Worlds currently active on", click on the [fetch] link and you can see the list of worlds on which the event is active.
(I know that your comments refers to more stuff than just that but this is a good example of the fact that things are moving forward)