Currently rigging in Character Animator is adding handles like dragger, sticks, fixed, etc. - see this tutorial as an example: Sticks & Dragging (Adobe Character Animator Tutorial) - YouTube. To do a walk cycle, currently you would either have to a) add sticks and dragger handles to the feet and drag them to animate a walk cycle, or b) make a frame-by-frame walk cycle in Photoshop/Illustrator and trigger it using the cycle layers behavior.
If you're talking about a full IK system, anything is eventually possible - while we have focused primarily on the face and basic limb movements up to this point, we realize a full "character" is a lot more! We hope to continue to build on this foundation, and provide tools and systems that make it easier than ever to get great, professional-looking results.
Thanks for the reply and the link to the video.
I second this ability to do pre-defined walk cycles with the stroke of a key. That would be very helpful in performances.