I'm excited too, by the prospect of new beastman camps. I hope that there at least three camps, corresponding to the three aggressive beast tribes of Amalj'aa, Ixali, Kobolds. Given the increase in presence of all of those beastmen, and the note:
More beastman strongholds and numerous other notorious monsters aside from those mentioned above will descend to plague Eorzea come patch 1.19.
I hope it's true.

Regarding the instanced versus open-world thing... I think have both some instanced and some open-world content is good. We already have Darkhold (and I hope that it is updated with some relevant gear to keep it fresh), and the new Ifrit battle (which is presumably instanced), so have three new open-world areas to explore works for me. As people have pointed out, it worked well in Aion, and there was only one camp, while here there will be three camps for people to spread out to. There are also a lot of possible hybrid strategies that the team could develop, where parts of the camp could be "overworld instanced" in the way that leves are, so I suppose we'll just have to wait and see!

On a final note, since the Ixali have been making inroads in to Coerthas, and have a camp set up in Fields of Glory, I wonder what is planned for Coerthas???