I understand completely what the author wants distributed computing to mean. I'm also very familiar with the scene he's talking about. In my time I ran Seti@Home, Folding@Home<- (? I think that's what the thing was called), the great internet mersenne prime search etc. I've even done the crowd-sourced distributed computing thing in Eve Online.
However this kind of crowd-sourced computing is a tiny subset of distributed computing. Unless you think (for example) that the author has got it right, and me and Leslie Lamport have got the definition wrong[1].