I read that you can only pick one or the other, but I have trouble believing these would be by themselves. I mean, if someone wants to do Fast Passes with older attractions, it would be kind of silly for Disney to fight them.
If they do tiers, I'd expect some of the other popular attractions to join the top tier. However, it may simply be when you select one, the other is automatically eliminated. We'll find out for sure tomorrow.
OT: I also read that they may doing an AP preview of Pandora in April.