I'm glad to be the first reviewer for this terrific book. I loved the male point of view, the tennis scenes, the premise of the two parallel alternate worlds. It's a fictional portrayal of the concept "Anything is possible."
This book pulls you right in -- the reader gets to sit back and enjoy the ride the whole way. Josh, the main character, is an engaging, good-hearted slacker who unwittingly falls into a different universe where he exists as a hard-driving, wildly successful but not very nice version of himself. It gives him a chance to really look at himself and discover who he is and who he wants to be.
I highly recommend it.