An excellent read that I imagine people will either love or be annoyed by. But, you'll know pretty quickly if that's the case for you. For me, this hit my sci-fi nerd-bones with just enough time travel stuff to satisfy without becoming overbearing. at it's core, this is a story about a son searching for his father in a convoluted time-stream. It's meta. It's got a lovable dog companion. It's got a great momentum (I read the last 120 pages in one sitting just to find out what happened and why it happened).
Anyway, I could write a more profound review, but you should save that reading for this book and not my review.