See thisin the biggest 3d-est theatre you can find. Who cares if the story has been done before a zillion times (Dances With Wolves, Pochahantas, to name a couple) - you go to see it . quite literally.
The IMAx I saw it in was vey comfy - but the interruption at the end as credits were just getting rolling to tell us how to leave very annoying.
Doubt that I was the target audience (late middle age female) - but its a must see.