Just saw Cameron's film AVATAR in 3d Imax. Truly a memorable entertainment experience.
Sure there are "messages" in the plot but they are hardly challenging or even original–the oppressive military/industrial complex which is more than ready and willing to displace and/or eradicate an indigenous people for their natural resources–the triumph of naturalistic spirituality as opposed to a creator God over such an "evil" empire.
What is surprising are the reports from around the world of the critical reactions to such benign messages. Each group or country or religion seems to see some aspect of the films subtext which is potentially threatening.
I guess if you are feeling particularly guilty about riping apart the environment over natural resources, you will take notice. If your religious beliefs are threatened by an more personal communion with the mother-goddess image of trees and nature you might have a problem here. If you think militaristic soldier-types are always justified in their decision making you would be upset.
If you are a feminist who are disturbed by the larger male indigenous Na'vi, I'm sorry.
But if you are like most viewers, you will sit back, marvel at the spectacular movie-making technology the possibility of love transcending background and origin and a warm nonspecific spirituality which should threaten no one.