This is work in progress so bear with me. If you want a link adding, just replay to this thread and Ill add it :)
General Links
Guild Wars 2 Official Website - Check regularly for upcoming patch information and blog posts from the developers/community managers/economists.
Official Guild Wars 2 Wiki - Not as comprehensive as the original games Wiki (yet) but can be very useful for finding out where things are and what they do etc. You can access the wiki ingame, by typing "/wiki *Search Term here*". For example "/wiki crafting"
Streaming Video
Official Arenanet Youtube Page - Not just adverts! Features developers guides to content patches, profession guides, beginners guides and more[/url]
Wooden Potatoes - Popular Guild Wars youtuber. Often features beginners guides and lore discussion. Does a lot of non-GW related lets plays as well, but its easy to ignore them.
Matt Visual - Along with Wooden Potatoes, one of the most popular GW2 youtubers around. Discusses a variety of topics and often does work with Wooden Potatoes.
Dulfy - Pretty much the most useful person in the GW2 community. Posts video guides to achievements, jumping puzzles, dungeons, patches and more. Also does a lot of SWTOR content, but dont hold that against her
Arenanets Twitch page - Pretty much the same content as their youtube page, but they do their livestreams here so its useful for watching PVP tournaments and watching their developer livestreams as they happen rather than 24 hours later on youtube.
Community Sites
Dulfy - Pretty much the same content as her youtube account, but also features patch preview information and some more indepth guides.
Guild Wars 2 Guru - I hesitate to call them a "fan" or "community" site because theyre owned and operated by Curse Gaming, but Arenanet do give them a lot of exclusive information and easter eggs about upcoming patches, so worth checking every now and then
Guild Wars 2 Subreddit - Mostly fluff at this point, but Arenanet do use it to chat to the userbase, so can be worth keeping an eye on.
Will update with additional links when I can be arsed :D