Spinner Cay is a magnificent place inhabited by the Vaycalians, a friendly merfolk race. Spinner Cay's blueish colors, waterfalls, and lanterns are a welcome change of scenery from the jungles, beaches, and pirate buildings you saw in Launch of the Screaming Narwhal. You can visit a local shop and library and even meet the queen herself. I never got tired of watching them plop down into the waters and pop back up. You get to talk with these Vaycalians but there's nothing really special, personality-wise, about them that stands out.
Unfortunately not enough is done to make you feel at home in Spinner Cay. There aren't that many characters here to chat with and you will spend more time outside the island doing other things. Spinner Cay could have been expanded with more set pieces, puzzles, and characters to interact with since it is the best looking place in the series so far. It would have been great to spend more time there rather than walking in jungles that look exactly like the ones from Launch of the Screaming Narwhal.
Now you will get to visit more islands, far more than LOTSN, as the game provides a map where you can direct the Screaming Narwhal to new places like Brilling Island and Roe Island. The place you will spend most of your time is the Jerkbait Islands, which actually consists of three smaller islands where you will meet LeChuck and the other pirates.