I wasn't especially impressed by this when I read it. Most of the (non-technical) advice seemed pretty obvious to me: try to make the images personal, mix in some candid or unusual shots with the standard poses, be ready for unexpected opportunities, try to capture the emotions of the couples and families.
But then I read some other wedding photography books, and thought about the weddings I've been in, and have to admit that Buissink is, if not spectacular to me, distinctly better than other wedding photographers.
Part of it, as he himself says, that he actually likes his job. Whereas most of the wedding photographers claimed to be artists who were just doing what they had to in order to eat, Buissink really likes weddings. He seems to really be excited for the couples and care about giving them photos that will make them happy.
It seems weird to me that the idea of having candid or even semi-natural wedding photos would be so recent, but it really does seem to have originated, at least as a professonial "photodocumentary" style, with Buissink. Other photographers who shoot in this style name Buissink as their influence. And almost every wedding I've been in or at produced very generic, stiffly posed groups with no personality or interest (the exception was a very casual garden wedding with a photographer who was a friend of the bride). I understand that every album needs a formal shot with the entire party included -- but in my opinion one or two of those is plenty.