In terms of the details of the movie I do agree that it seems there were parts that were evidently left out, and since Cameron is a perfectionist I’m not surprised at all to hear that so much was thought out. As much as I think a prequel would be nice to satisfy the detail-pickers out there, I don’t think that it would happen, just because you wouldn’t have Jake and Neytiri running around together on Pandora. As much as people gripe about the plot, for the most part it seems everyone got quite attached to the main characters and their pairing. From what I’ve heard at least one of the sequels will be the two of them exploring Pandora more which means more pretty glowing thingys.

In terms of the footprint thing, I actually think it might be a response of the plant itself. There are plants which do respond in physical or biochemical ways to pressure, so it wouldn’t be too farfetched for plant matter to fluoresce in response to the pressure of a footstep.

I still know a handful of people who haven’t seen it yet, so I’ll probably end up seeing it at least one more time.

Pandora itself is a moon of the gas giant Polyphemus. As we see from several night sky shots, the giant takes up a large proportion of the sky. That the reflected light off the surface of the giant would light up much of Pandora’s night is something that is very plausible. Its blue colour also explains why much of the Pandora night is tinged in blue.

Still haven’t come up with a satisfactory explanation to all the bioluminescence though.