So very sad to hear this. Think it will take a while to come to terms with the passing of such a character in swimming.
His love of swimming was infectious, and through his books he touched so many peoples lives, mine included. He inspired in them a love of swimming through his love of the sport and his eloquent and insightful writing.
He was at a triathlon expo in Manchester UK a few years ago, and I just had to go and meet him. In person he was just as passionate about TI and swimming in general, and was a very friendly and approachable guy.
He will be sorely missed, and is irreplaceable as the face of TI.