Peter Nelson's treehouse books are always inspiring, voyeuristic, and FUN. This is his best book yet. Not a How-to (he's done those) although he does briefly touch on the latest in treehouse engineering and there is a wealth of contact information in the back of the book.
The photos are very clear, well composed, and this time we get a lot of views and angles. His last book was a bit stingy with the photos, leaving me wanting another page of pictures. This book gives it to us. The design quality of the treehouses featured is also unsurpassed. He doesn't just show us money-no-object projects but also beautiful aeries built by a homeless man or salvage junkies. The book's continuity comes from all of these treehouses being gorgeous works of art built with an artists eye. It seems that by placing a house in a tree, it frees the imagination (and the voice in your head who says "you can't do that"). More passionate architectural creativity is in this book than you can find anywhere else.
Pete narrates the book, letting the reader in on the impetus behind the owner's flight of fancy. His words add to the visual story and brings some details into focus.
The best Treehouse Design Book ever printed. Should be in every library.