Firstly, it seems that I am always slightly vibrating all of a sudden while using full body tracking. Friends with FBT also reported seeing themselves as vibrating, but it seems to be a local issue.
Also, if you're a full body user and you lay down with your legs out in front of you and try to look from side to side with your head, you'll notice your legs will start trying to follow your head movement from side to side. This was not happening prior to this patch.