Great game and design, but too easy ! WITP !
I feel this game is a way to introduce younger gamers to platforming games. And by younger I mean really young. I recommend this game for a child who has difficulty with a more complex platformer, take Mario Galaxy for example.
It also has a special atmosphere that is hard for me to describe. The lullaby style music makes me feel nostalgic. Its a very relaxing universe, but not a boring one.
I recommend you rent this game for a weekend only. It will be all the time you need to play through it and experience the special atmosphere it has to offer.