On his Flickr photostream, lk.lkaz posted several GIF animations of his "running" Lego Technic Kinetic Animal Frame prototype. The 4-second GIF animation shows how it works. A small, continuous 320x240 GIF loop appears below (from his Brickshelf gallery); he has a larger 800x600 continuous GIF loop that you can see here (but is not deeplinked here in the interest of bandwidth).
He wrote that he "...tried to make a cheetah-like mech, but many problems remain :(
1. There is a gap of the stroke speed bitween the front and rear legs.
2. The front and rear legs can't cross each other.
3. A static head and a dynamic tail mechanisms are needed."
His MOC was "Inspired from
Cheetahs on the Edge--Director's Cut by NATIONAL GEOGRAPHIC
by Andrew ChaseLEGO Knuckle walker KONG by ใดใ(PIKO or PICO) (.mpg) ."
He made GIF animation details about the backbone, rear leg, front legs (all below), and gears (above):