4,5 stars. 
 I really like science fiction that ask big what-if questions and then runs with it. Think about all the repercussions of that idea. That thinks about all the possibilities and then explores them though the plot of the book. The Long Earth does just that. 
 If you want to see what the book is about go read the blurb. But to put it every shortly humanity discovers how to step into an infinite number of parallel worlds devoid of human life. Which to me is a fascinating premise. For one thing this is the end of many resource shortages. 
 Though the plot does not start until pretty late in the book it pulled me into the story. For the first 100 pages I thought that I would be perfectly happy without any real plot. The story is comprised of a main story interjected by a lot of vignettes. Some vignettes has repeating characters, such as Monica Jansson while others are one of stories. The vignettes and shifting point of view really works in this story. It helps tell the broader story of how the stepping into parallel worlds affects the world, without annoying me, as shifting points of view often does. 
 The story holds a true sense of wonder, the kind of wonder science fiction is suppose to hold. The virgin worlds parallel to Earth are just amazing. There as some very short but effective landscape and animal descriptions of all the wonders of those worlds. 
 Parts of the books was impossible to put down while others were slower and quieter. But all of it was very enjoyable. 
 The Long Earth is one of the more philosophical books that I have read in quite some time. It has clearly been thought though quite a bit. It talks about the economic consequences, the sociological ones, the political implications. It thinks about a the longer term consequences and the story is told over about 15 years, which is quite a lot longer than most books. 
 The last 25 % of the book made it impossible to put down the book, the plot really kicked in and the mean authors left me on a freaking cliff hanger. Now I have to read the next book, but I wanted to do that anyway. 
 Read more of my reviews: http://www.mackat.dk/book/