I read a rumour that Plaguemarines were getting a special rule in the new codex called 'stoic' which meant they could charge after rapid firing but couldn't sweeping advance. Can't find a rule called Stoic in the book but slow & purposeful would basically do the same thing. All the Nurgle Deamons have S&P so it seems likely we'll get the same. I quite like that idea, you loose the ability to Overwatch & run but it's kinda Nurgly!
Has anyone noticed the new 'defensive' grenade rules? If your being shot at from 8" or less you gain the stealth rule. Very characterful!