This book is currently on its 5th consecutive renewal from our local library. It is a huge hit with my nearly 2 year old and we read it every night before bed.
Every 2 page spread has a number (from 1 to 10) with the digit, the written number and a simple rhyme on the left hand page which matches the picture on the right hand page. For example there are '2, two snakes with garden rakes', or '10, ten bees pruning trees'. Each of the rhymes are very amusing and beautifully illustrated. The final double page spread has a detailed picture with all of the animals on it.
When I read it with my son, I trace the number with my finger, count the number of animals and then read the rhyme, so he hears each number 3 times, and sees it as a word, a digit, and sees / hears me counting them. This is such great exposure to counting and numbers.
I highly recommend this book.