Why aren't Japanese animation studios switching to digital art for production instead of pencil and paper?
Here is an interesting article about how the anime production process works.

Here's an excerpt I found particularly interesting (and relevant!):


  [T]he crucial thing is that the frames are still initially drawn by hand, and no in-between animation is simulated by a computer. There are some animators who draw 2D animation directly onto computer, but in anime this is largely restricted to in solo animation productions rather than commercial anime. The industry prefers this because the animators are generally more comfortable and able with this method, and it allows easier checking and correction of frames under sometimes tight schedules.