1- The illustrations are fun, bright and engaging!
2- It's a reader book with very basic wording, yet not boring.
3- There's an unexpected and clever little "development" in the book that I appreciated very much and won't spoil for you with details. Otherwise, you're pretty much just enjoying pictures of mice on ice the whole book.
And it's as simple as that folks! Fun, easy reader book that is both wintry and engaging! Readers usually suffer from one two problems: they are either commercialized character books (which annoy me aesthetically and concern me parentally, when fed in excess to children) or they are dry as dirt in their story lines (if you can call a cat sitting on a mat a story). Usually they are both. I understand that the stories HAVE to stay simple to some extent but this is proof that they don't have to be banal. A refreshing change up.