The skill bonuses from skill-modifying clothing (this includes things like the fancier sorts of condoms, aviator goggles, etc.) no longer stack if you wear multiple pieces of that clothing. For example, you used to be able to stack lab coats and get +2 science for every coat you were wearing. Now, you'll just get +2 no matter how many you wear.
Beware: Skill penalties from clothing will still stack. If you wear three pairs of earplugs then you'll still take -6 senses.