As a Dutchman who has seen lots of different cultures (America, Australia, several European countries), it's amusing to see how others see us.
It was very funny at times, but as stated before it was also bashing at many times.
The one thing that I got a problem with, is when information is incorrect; if you don't know alot about a subject, don't write a lot about it as if you DO know, because that's a little insulting. For instance that the Dutch language comes from German; absolutely insulting and extremely incorrect. The writer obviously didn't do his homework. Dutch is a Germanic language, but so is French, and is French anything like German? I think not. Dutch is completely different too, and it is definately NOT easy for Germans to speak Dutch or vice versa.
As a matter of fact (no offence to my German neighbors, but I have to mention something about the war)during the war Germans were hiding here and pretending to be Dutch, but they caught them by letting people pronounce the word SCHEVENINGEN (a city near The Hague), and it's impossible for Germans to pronounce this word correct (also impossible for English people), so that's how they were caught.
Also the bit about child raising is very exaggerated. Yes we believe in the freedom of kids to explore their own ways, but we won't allow our kids to smear dirt on other peoples coat without correcting them, that's BS. Maybe he did experience that, but then it's an isolated incident, and it is then wrong to say every kid in the Netherlands gets this kind of raising.
I also found the book not exactly about the whole Dutch culture, but more of the northern culture.
Our tiny country has 12 provinces, 2 of them are named Holland (north and south).
What many foreigners dont know, is that our country has only one name THE NETHERLANDS; it is often refered to as Holland, but again that's incorrect, Holland is a province not a country, it is a province of the country The Netherlands.
This mistake has been made for centuries; since the provinces of Holland got great fame during the Golden ages, and Amsterdam (North Holland) became very important in that time, as well as Rotterdam (south Holland). And because the main international traffic went through those provinces, they always refered to it as Holland, and now they still refer to the whole country by saying Holland, which is incorrect.
This is not mentioned in the book surprisingly.
And like all the 50 states of the US have different people with different habits, our 12 provinces are different too. I live in Limburg (home of the Limburger cheese), and the people here are completely different than the people in Holland, but unfortunately Limburg isn't mentioned in the book.
Many Dutch people split the country in 2, it is horizontally divided by 3 main rivers, and people always speak about the people "above the rivers" and underneath.
Underneath the rivers the people are very hospitable, giving and caring, above the rivers people are pretty cheap and stingy; and it's there where you come by during dinner time, and not get invited to join dinner as well; underneath the rivers you will be stuffed with food until you can't walk anymore. My point is, the book is a narrowminded view of the provinces of Holland, not the rest of the country. (We even got big modern toilets in the south, haha).
It was funny though to read about the upperdeck in our toilets; I never knew that was a Dutch thing, but as I thought of it, I indeed never saw an upperdeck abroad, haha.
The traffic things were quite correct too, and very funny to be confronted with it. Also the public transfer behaviour were quite accurate, and again funny to read.
All and all, a funny book, but don't take it too seriously and please don't let it influence you in a negative way about the people and culture. If you wanna know for sure, just drop by, and see for yourself.

I borrowed this book from a collegue about 3 months after moving from the UK to live and work in Amsterdam. I found it amusing and at times quite accurate, but I was too often turned off the book by it's rather unpleasant tone. Of course, it's meant to be tongue in cheek alot of the time, and alot of the time it succeeds, but too often I felt the joke to be in rather the wrong spirit, and the tone rather sneering. Although I don't know, I would guess the authors are American(there is no offence intended here - just that I find alot of American-media humour rather jarring in the same way - the people themselves on the otherhand are often as not delightful)- or else they are Continental Europeans who have watched too much US television.
There is a very amusing section on houseplants and the enthusiasm the Dutch people show for them, which I find increasingly well observed the more Dutch homes I am invited into.

After looking at the reviews of this book, I've noticed an interesting trend: Primarily, the positive reviews of the Undutchables were written by Dutch or people close to Dutch culture, while negative reviews were often written by those who are not close to Dutch culture and Americans who are worried about being PC.

My personal opinion is that the Undutchables is a humourous account meant to be read by people who are already otherwise familiar with Dutch culture. It is not a travel guide. While many of its points are true, it is not to be taken seriously and any traveler should form their own opinion of Dutch culture, possibly using the Undutchables to alleviate some culture shock and create a bit of understanding. You would be better off buying a travel guide of the Netherlands if you want an unadulterated view of the country, but the Undutchables offers a lot of character.

I am an American married to a Dutch man and this book was recommended to me by 2 Dutch people. Many other inlaws and friends have now read it and everyone finds it good and unoffensive. My mother, who knows little about Dutch culture, is the only person who seems confused by the book and a little put off by its negative points.