Paul Motter, the editor of our sister forum CruiseMates just returned from the inaugural cruise aboard Splendida. You can read his reports and see tons of photos here
As for the ship's deck plans, it's odd that MSC doesn't have them on their website. However if you go to one of the popular on-line travel agencies you will find the deck plans. I just located them at cruise411. Travelocity doesn't have the Splendida listed yet.