Here's a really great interview with Film Freak Central. Makes for heavier going than some of the earlier interviews, but if you're of a literary bent and like taking a deeper look at things, do have a click.Sample Q&A:

Isn't that the key? To trust mystery--to trust that the things that are pleasurable to me and scary to me are also that for others, without explanation?
You're absolutely right. That's what I try to do. If one is doing art, that's what I think that you must try to do. There are other functions for film and people do it for all different reasons, but if you were to ask me why I do this--which is you know painful sometimes and hard all of the time--I would say that if you're doing this for art that the only responsibility that you have is to try to get close to your truth. This thing I read that Isadora Duncan said that really stuck with me is that she strove her whole life to make one authentic gesture and I think that's the truth of it. Here you have this world-class artist and that's all she's trying to do and implied in that is that she failed, but that it's her goal throughout to find this thing that's true. I saw this thing, this dance troupe, really acrobatic, and the notes in this show had the choreographer saying that she came to a point where she observed that any movement that she did should take only the amount of time and effort it took to do.

Some of CK's recent comments have made his film sound... shall we say, less appealing than I'd hoped - especially after the trailer lifted my hopes above what they were when I read the script. This interview only makes me want to see it more.