The Friday cephalopod always makes me smile, but this one especially so.
Actually, what makes it adorable is the ratio of tentacle length to head/body and the size of the eyes, I think. Just like with a little kitten, a puppy or even a human baby. I know it as "Kindchenschema".
I second Flo. It's the same premise that Japanese "Chibi" style animation is based on.
That being said, it's the spots that make me SQUEE!