Didn't know quite what to expect, but they did 3D right on this one - previous Imax 3D movies I have watched really didn't provide that true extra pop - this one had people reaching out to grab vines, and I even flinched/ducked when there was a projectile that 'was heading towards me'.
The sound was fantastic, though loud towards the end - I found that I walked out of the theatre with diminished hearing.
The plot is fairly typical and predictable, as I had read beforehand, but the A/V experience really made this worth seeing.