I don't expect anything great. In fact I have stopped playing all together because well, lack of content and how the game feels empty. I only came here because I saw this thread on the main threads page and thought, maybe someone knows something about it and I am curious.
Reason why I don't expect anything great is that we have already have a year for them to be done dripping holiday and seasonal content as "extra content". The one year mark was back in March. It is June now. Whatever update that is coming, I feel like it is going to be pretty small.
Maybe others are right and there will be something a little bigger like how they added swimming last year. However, a one year wait doesn't seem like that it matches. And considering the game takes place on a deserted island, swimming was kind of a give in. I am just surprised it wasn't in the game from launch. Even if it was just limited on how far from the island you could go.
That is just my feelings on it and I am sure other people have other perspectives which is absolutely fine. At the end of the day, I just feel like there isn't anything going to be all that great. Unless it is paid DLC.