There is a simultaneous discussion going on about the brown leather in the 2017 Highlander thread. The consensus is that it will be available for the Limited and the Platinum based on multiple sources.
Regarding the color options, I think it's safe to say that you probably won't be able to get brown leather with the body colors that clearly don't match like gray or silver. You can depend on white (as in the hybrid test drive), green, and probably red and black and one would assume the toasted walnut. My guess is not with shoreline blue - I don't think that brown leather would go with that. As one of the other posters mentioned, you probably can check the available color schemes of the other models.
If you really want brown leather with a body color that isn't available then perhaps you should reconsider. But, hey, I was hoping to get an SE in Jade but they only seem to offer green bodies with beige interior and not black or grey so what do I know - I probably have bad taste.
As far as ordering goes, I don't think anyone here has reported that they have gotten very far with any dealerships. They seem to all still be in the "Why don't you consider a 2016 so you don't have to wait?" mode. According the Toyota rep in the hybrid review video, pricing isn't expected until the end of October. There's really no excuse for that. Why would you not know what the prices will be?