The film has been playing on HBO for a while, so you may have seen it there. It's very good -- but terrific as it is on TV, the full version seen as intended and on a big screen is something else entirely. And if you haven't seen it at all or only seen it on TV, you'll have another chance to see it "properly."
The film is returning to theaters on December 7, 17 and 18. (The latter date is exactly one year after my article about having seen the documentary.
Better still, it will include the great "making of" featurette, about 20-30 minutes which fascinatingly explains how it all was done. Plus, there is an introduction by Peter Jackson.
If you have interest in seeing this special theatrical version -- and again, it's remarkable, and also has the "making of" production -- you can check this link here for your zip code and find where it will be playing.
Here's a brief trailer. It doesn't begin to do the documentary anything close to justice -- but -- it gives you a touch of an idea of how unique this is.