We let baby push this around today (when he changed it to the upright position) and seems to kind of get that she can walk with it.  She pushes it back and forth, but doesn't really take many steps with it.  As for an update on her walking abilities, she is cruising very well along furniture and pulls herself up on everything.  (Not up an over, just up...thank goodness).  She can take some steps on her own, but has taken some pretty good tumbles, which of course means that mommy and daddy go running to her to coddle her:)