This walking animation is actually sixteen frames (well, eight frames on twos). It looks very good. The only thing I'd change is that the character doesn't bounce up and down enough as he walks. When I planned it out it looked like there was enough up-and-down movement; I didn't compensate for the amount of exaggeration needed.
This animation was drawn using paper, a pencil, a lightbox, and a pegboard. An x-sheet was used to plan the timing. The frames were captured using a mounted camera and everything was animated in DigiCel Flipbook.