If Spielburg loses this poll, I'm going to boycott the polls for the rest of the contest.
I absolutely cannot conceive of how Spielburg could lose to Nolan.
Here are the first 5 top ten lists I came upon.
1
2
3
http://www.filmsite.org/directors.html
4
5
These are just the first five lists I came upon in order that they popped up. They are by no means comprehensive, and no one list is representative, but I think that, taken together, they might have some meaning. They all have two things in common.
1. Steven Spielburg is on it, in many cases as the number one spot.
2. Nolan is not.