I wonder how relevant an Avatar attraction will even be once it has been built (which would tkae some time, no?). I mean, the movie is already "yesterday's news" so to speak, and it is only going to get staler.
Star Wars (and Harry Potter at Universal) are more enduring and make more sense to me as film-based attractions. Heck, even more Muppets stuff at DHS would make sense, given the new mpovie coming out this November.
I'd check out any and all new attractions, but this one isn't conjuring up any real excitement for me, and neither is the princessification/fairization of Fantasyland, either.