Inception Ending Explained. Yes, This Will Ruin the Ending if You Have Not Seen It

Let's skip the introductions here.  Do I really need to say spoiler alert?  You've seen the movie.  You know the ending.  You are curious to discuss. 

So the big, lasting piece of the discussion is the last shot and what the cutaway from the totem means.  Was it all a dream?  Or has Cobb returned to reality?  I have seen 6 separate explanations of the film.

1. All of Inception is Cobb's dream.
2. Everything after Cobb's sedation test is a dream.
3. Saito pulls a "Mr. Charles" on Cobb.
4. Adrienne is a therapist and is the architect to cure Cobb.
5. We see reality during the film, but the end is Cobb stuck in limbo or a dream.

6. We see reality near the beginning of the film, and Cobb is in reality at the end of the film (the happy ending).

Yet with a film that has 5 distinct dream layers, there is a deeper level that no one is considering.  So I shall consider it. 

Cobb's children are older, as we see in the casting of the children.  The kids are cast in two different sets, two years apart.  So the children Cobb encounters at the end have aged.  Would they not have stayed the same if it was memory or dream? Cobb has won and entered back into his reality.  The happy ending is his.

Yet Cobb's reality is Christopher Nolan's dream.  It is a reality within a dream, and we, as viewers, are experiencing that reality through the sharing of Chris Nolan's dream. 

We cannot see the final totem fall.  It spins perfectly in the dream state infinitely and never even wobbles.  In this case, it wobbles, and we are abruptly "awoken" not before it falls, but as it falls. 

The cut signifies not that Cobb has indeed returned to reality, but that Cobb and we as viewers have both returned to reality.

Cobb is the protagonist.  We experience the film through him, so we share his totem.  Once it is established how the totem works, we have begun to share it since we know its secret.  Notice that Nolan does not let it fall when he is splashing his face--it doesn't seem to make sense in the context in the film, other than to confound, but instead, I think it is meant to preserve Cobb's reality and our dream state as viewers.

So at the end, the totem spins.  If it falls, we are in reality (the real world), and it proves that Cobb is in his reality.  So it wobbles and as it falls, we are thrust back into a darkened theater and do not get to witness Cobb going back to the table and seeing it on its side. 

I do not believe for one second there is an "open ending" to the movie.  Nolan doesn't appear to work that way with his other mind-benders.  So I would like to think that as complex as the film seems,there is a definitive answer to this "maze," but as we learned in the film, only the architect (Nolan) knows that path through the maze so that projections or dream-sharers (us) cannot navigate it easily.  The film is the maze of his dream. 

Either way, Nolan has done quite a trick--performed "inception" on us, planting an idea that grows like a virus . . . the ending was his idea, but has created an outpouring of theories (including this one) that makes us think the ending was our idea.  Neat.  I believe it when I hear it took him 10 years to finish writing this movie.  It seems that damn complex to me. 

Any other good ideas out there?  Let's shoot some holes in my meandering theory until I can see the film another time or two.  Fire away in comments.