I'm kinda worried that swimming won't be back. I haven't seen it in any game footage and I noticed that the encyclopedia only showed fish and bugs. Now it might be that the deep sea creatures part of the encyclopedia is unlocked after you catch your first one, so that's why it wasn't shown, or it could be that they are just lumped together with the fishes. Also, I didn't notice a deep sea creatures section in the museum either, but I haven't seen all of the PAX footage so maybe it was shown there? Anyway, if swimming won't be back, I won't be too disappointed, but it would be nice to have it back. And if they do bring it back, I hope we can swim in the rivers and ponds too! But in the end, the game looks fantastic to me and I'm sure I'll love it with of without swimming!