Wtf is Up With the Number 9?

Is it just me, or does it seem like 9 is everywhere these days? I started wondering this when I first saw a preview for 9. Set in a future where humanity is screwed, 9 little doll-like things run around and fight machines. Or something. In addition to that one, Daniel Day-Lewis (a personal favorite actor of mine), just wrapped shooting NINE, a film adaptation of the 1982 Broadway musical.

Before that, there was the hardly watched (though I both tuned in and enjoyed) THE NINE, which ran on ABC for a short-lived 13 episodes. The plot - 9 people are held hostage during a bank robbery; something (which, had the show lasted longer, viewers would have found out) happens that creates some very weird character dynamics between those involved.

Some other imdb fiddling brings up a handful of other, sometimes lesser known 9 titles. NINE LIVES (2005) chronicled events in the lives of nine women. In 2000, there was NINE - a psychological thriller by Jane Shepard that I've never heard of. 9 SOULS is a Japanese prison break movie from 2003.

Then, just today, just a few minutes ago, I clicked on over to Done Deal Pro. What is the very second logline I see?

Title: I Am Number Four
Logline: A group of nine aliens flee to Earth, disguised as teenagers, when their home planet is destroyed.
Writer: Al Gough, Mils Millar

More number 9! What is it about nine that makes the number so special? Nine circles of hell. Nine choirs of angels. Nine as a perfect number in Hinduism. Nine innings in a baseball game. Nine planets (when I was a kid) in our solar system. Nine as a purity grading scale for metals?

I just don't get it. Maybe it's all a coincidence. Look out vampires, Nine is the new Twilight.