My first thought upon reading a page of this was " it's a greeting card; a particularly charmingly illustrated greeting card."
My second thought was "that's brilliant!" This is stuff many parents are awkward verbalizing to their children: maybe they've never heard an adult say such things to a child, or maybe they know what they want to say but can't find a way to make it into a natural conversation. Parents who want to express their love may have a tremendously hard time imaging a script of what to say, as well as how. This book, and the others like it, provide parents with an easy way to practice saying loving, positive things to their children. Or maybe it will serve as a reminder to those already conversant with affection, a deliberate moment to stop telling the child how to behave or what to do, but just take a moment to appreciate the closeness.
Reading aloud to my kids was a huge priority for me. I read compulsively, so no surprise, but it became a whole rich, shared experience. Going to the library once a week, the bookstore from time to time, book fairs, book sales, a special children's book-signing, they were activities we could share the way other families might share a particular sport. I tried to never skip those nightly readings, and I let them choose the books, and yes, that meant reading a lot of drivel I couldn't stand, and abandoning books that weren't working, and the seemingly endless recitation of favorites. But look at what I have now: two adults who still love reading for fun, who enjoy reminiscing about past reads, and suggesting new ones, and talking about books and talking about everything else.
Really, it's all about snuggling close and saying "I love you" over and over and over again in as many different ways as we can find.
So yes, it's a lovely greeting card, and a reminder to actually say out loud how much love you have. Every new parent needs some books like this, almost as much as they need diapers.