There is no way to judge it unbiased, it is Tim Burton after all.
Here we go, my totally biased, uninformed and therefor rather unhelpful conclusion after reading: This is the cutest thing ever. Adorable in a dark, slightly sick way, of course. Think Addams Family here, they would have cried over these touching little gems of poetry and story telling. If you think somewhat like them, you will love this.
To say something a bit more impartial, the poems and illustrations that fill this collection complement each other perfectly, all clearly showing the hand of its creator. And in their weirdness, their twistedness, they all (most) are build on very serious matters worth checking out even though the quality of the poems is probably, ehm, discussable. But when you think about it, this naivete might travel further than any more sophisticated writing could.
My favorites were "Stick Boy and Match Girl in love", "Brie boy" and "James", though it is hard to name titles that stick out, the charming appeal is the whole of all of them.