If there's one thing you learn about dragons, it's that they're almost always accompanied by reams of lore. For reference, see: The Elder Scrolls, Dragon Age, and Guild Wars 2. The latter's long and tangled history will be further explored in next week's update. Cue trailer, which contains spoilers for last week's episode.
If you're not a regular GW2 player, very little of that will have made any sense. Don't worry, it's just dragon stuff.
From a content standpoint, last week's episode was great: filled with a complete new zone, new boss types and a surprising story path. Hopefully ArenaNet can keep up that momentum as they move close to Season 2's conclusion.