Best Director?!

Best Director?

I would say Darren Aronofsky (Pi, Requiem for a Dream, The Fountain.)
Who do you think?

Aronofsky is a very good director. "Best" though, is particularly difficult with directors, because film is such a wide and varied medium that it's impossible to compare the work of all the great artists in the field.

Some other great directors:
Scorsese is a great director, though I wish he would add a few more colors to his artistic palette.
Spielberg is a great director, though I wish he would show a little more subtlety and restraint sometimes--his audience can be trusted to "get it" without being hit over the head.
Clint Eastwood is very good with casting. He chooses great actors, leaves them alone, puts great storytelling and technical people around them and gets great performances every time.
Alfonso Cuaron is a director with a wide range: children's films, the best of the Harry Potter series, "Children of Men" "Y tu mama tambien" etc. The man directs films in two different languages in all styles and they are all really good. No "duds" in his resume! (Can Spielberg say that?)

There are a lot of other directors' whose work I really like (Nair, Almodovar), and a lot of people who are just beginning to direct (Anand Tucker) who are doing great things, too. I loved "Good Night and Good Luck"--who knew George Clooney could make such a little gem of a movie?

It's a good thing we get to have directing awards every year, so we get multiple chances to reward all the great work people are doing!