I can talk to a few NPCs who don't have anything to sell or any messages, but there's no way to proceed with the game :/ Solved: Turns out when you talk to the person with the icon above her head at the farm, you have to click the item at the popup. If you dismiss it by default rather than clicking it, because you're apparently not paying enough attention, then you can't do anything in the game, that is until you reinstall the game, come back to it another day to talk to blizzard support, and then get sent here, and then click the thing you were supposed to click in the first place by accident.