I honestly hadn't put that much thought into what I would want to know, thinking I wasn't really worried about spoilers (although I didn't want to see pictures of Pandora before going). I know I don't want to watch ride videos or anything, but now I'm thinking I don't want to see too much since we're now going for a kid-free weekend in late October (WDW). Although, with seeing some of the photos (one with all the Cast Members, maps, the old artist rendition/predictions (suddenly drawing a blank on the right term), etc.), it won't be a huge surprise (I think?). But with a trip planned for 2 months after it opens, I'm thinking I may avoid a lot of it to the extent that I can.
On the other hand, however, I am very interested in what the news coverage will be like of the opening(s), how things are going, crowds, wait times, etc., so I don't know how easy it will be to follow that stuff without "spoilers." I guess we'll see.