The bottom half of the frame is clear and clean, and gradually goes out of focus towards the top. It is not artistic, and happens in many shots in that consistence gradient. It was either poor film scanning, or filming. For how much time and money they spent restoring it, and how amazing it looks when it's flawless, it's disappointing unless it really was out of their hands in terms of what they had archived.
Also in trying to get rid of every piece of grain they really destroyed some of the detail of the cels. I watched the Pixar Story and seeing some classic 2-D animation from Disney in HD was amazing. Incredibly clear and vibrant even with all the grain, scratches, dirt, hair, cel warping. Here's a shot
courtesy of lyris.
Can't wait for more 2D goodness, and I hope all their films get this treatment.