It appears like they've done it in CG and tried to make it look like hand drawn animation, therefore looking rather 'unfinished' becuase there is little textures added.
Just saw the trailer, and the animation style reminded me of the old Dreamcast game Jet Set Radio. Using cel-shading, if memory serves. It really shows up on characters like Snowbell, the extreme white-to-grey and so on. Quite cold and soulless for a film. Having said that, A Scanner Darkly, judging by the trailer, is making an ingenious new use out of it. And as for the plot? Seems awfully Beethoven's 2nd to me, in a way.
personally I like Cel Shading when done correctly... Second Renaissance from the Animatrix used it quite well, and I quite enjoyed the MTV Spiderman series where most of the human characters were point-location based motion capture with cel-shaded characters, with only Spiderman himself being more traditional CGI.
Yah, I don't understand why they used this type of Animation. Normal 2D Animation would have better, though this film kind of seemed like a pilot for a TV series instead of an actual plot for the film.