Like all books I was hoping for something that delivered a little bit more than the man pages and online docs. Sadly this wasn't really the case. Now I'm not saying that ‘Running Xen’ is a bad book. It's not. It's just missing that “something more”, that “je ne sais quoi” (I cannot believe I've just typed that and not removed it). If you're going to somewhere without man pages or online docs, then it's an invaluable reference.