I bought this book for my daughter 2 years ago. She's now 2 1/2, and this book has been read to her hundreds of times (at her incessant requests) to the point that it is now covered top to bottom in scotch tape! I'm currently online to order a second copy for my 6 month old son (and no doubt to the delight of my daughter!). I can't recommend it enough!
I'm surprised to have read a complaint about the illustrations - I (and my wife, and my daughter, and everybody else who has seen the book at our house) think they are wonderful: bright, detailed, and above all, contextual (something I've wondered about with other nursery rhyme books). I think one should take that comment with a pinch of salt; there's nothing in the least bit inappropriate with the illustrations (the cover is itself an excerpt of the style in question).
My only wish would be that they could print this book on laminated paper so as to avoid all the wear and tear that it receives as our children's favorite! I for one would be happy to pay extra to preserve this book for their children one day!