Well this is book for Young Adults and therefore I must admit that the style was a little bit problematic for me. I guess because I'm only an "adult". It's very simple, very on the level of the main character but after a while I get used to it and I might say that this naiveness was even charming. Big part of the book is like as if we are waiting something (big) to happens, the main thing but I wouldn't say the book is boring; again it was charming.
I usually find myself very irritated with the child character who is completely (and impossibly) ignorant about the things around them since it's usually not convincing at all. But I think he is one nice exception. Bruno is lovely constructed character and his views are very convincing. Occasional sparks from the world of adults are giving reader nice background picture and contrast with readers understandings and Bruno's ignorance (or misunderstandings) are really lovely. So, indeed Bruno is very likable "young man".

I will not tell anything about plot (neither will give my rating because I don't think I'm competent since I'm only "adult") but instead will type what it says on the back cover,probably the best book blurb I saw:

"The story of The Boy in the Striped Pyjamas is very difficult to describe. Usually we give some clues about the bookon the cover, but in this case we think that would spoil the reading of the book. We think it is important that you start to read without knowing what it is about.

If you do start to read this book, you will go on a journey with a nine-year-old boy called Bruno. (Though this isn't a book for nine-year-olds.) And sooner or later you will arrive with Bruno at a fence. Fences like this exist all over the world. We hope you never have to cross such a fence."