Now there's the end of an era in practical effects. The guy was an absolute master of his craft. Variety has quotes from several of Winston's colleagues and friends, including Steven Spielberg and Arnold Schwarzenegger, as well as producer Gale Anne Hurd. Notably absent is James Cameron himself, whose Terminator sketch Winston brought to life and for whom Winston built the power loader and Alien queen; I don't know if he was unavailable, or just couldn't get a statement out in time. It's my understanding that Cameron and Winston were very close, so the latter may be the case -- Cameron is a famously difficult guy, but those who have few really close friends often feel the loss of those few tremendously. (ETA: Cameron sent an email to Harry Knowles.) Winston has apparently suffered from cancer for seven long years. That must have been a terrible period for Winston and his family; he kept it as quiet as he could, and this longtime fan hadn't even known he was ill.
His company kept producing great work, even as he suffered. It was the talented designers and fabricators at Stan Winston Studios who built the suit for Iron Man.
Stan Winston: a man who knew how to leave the game when he was on top.