I peripherally heard about another Tylenol recall and assumed the recall was prompted by tainted medicine or something. Anne just sent me a link to the story and it is apparently usability related. The syringe-based dosing system, called SimpleMeasure, seems to be difficult to use. Here is what NPR says:
the “SimpleMeasure” dosing system that’s supposed to make it easier to fill a syringe with the right amount of the grapey painkiller and fever-reducer is too complicated for some parents.