Nintendo's Super Mario 3D World would have not been that attractive at first sight if not because of its set of enthusiastically-created artwork pieces. So, what are these interesting artworks? Let`s us give you just the ten most interesting ones. (You`ll discover the rest when you play the game.)

New Worlds
It's called the New Worlds, but it looks like just the classic Mario worlds—21st Century version. In the artwork you can see the grass which filled the foreground, the sunken ship, and Big Bully standing on the snowy level. In the background we have the theme park, tropical island, volcano, etc. Over-all, the artworks portrays the picture of the “worlds” as the player goes from one place to another or play from one level to the next.
 

The Bullet Train
Did you miss Boom Boom and Pom Pom? Well, after appearing as airship bosses in Super Mario 3D Land, they're back on track for a level set on a train. This Bullet train could be one of the end levels which you have to run along as you pass that Thwomp to get to the end, where the boss is waiting.
 

Sunken Ship
The idea for this level was probably taken from Super Mario 64 or New Super Mario Bros. sunken airship. Talking about Super Mario 64, Plunder, The Sunken Ship in Jolly Roger Bay is a star challenge in which you had to go deep into the ocean to the shipwreck, remove the eel, get inside the boat and unlock each chest in correct order. When everything was done perfectly, the sunken ship will rise and you'll be rewarded with a star.

Green Star Bonus World
So in this world, your role is a toad, not Mario. And this Toad is similar to that which belongs to Toad Brigade from Super Mario Galaxy. If you have watched the trailer for Super Mario 3D World, you might saw him going around a pipe in the world map.

Head In The Clouds
Just like in grassy, snowy and lava levels, there are also bonus cloud stages. However, if you play multiplayer, there's only one prize in the end so you need to run the race in the clouds to get that precious prize. Exciting, isn't it?

New Enemies
Since it's a new version, we also expect new enemies. In the artwork, the first one you notice is the bird, wearing shades and preying a snail, which looks like just an obstacle rather than an enemy—just like Piranha Plants, which would just peck at you as you run past them. Another enemy is the bug. You've seen it in the trailer. Together with other bugs, it would attack you.
 

Big Bully
The boss in Lethal Lava Land from Super Mario 64 is back to attack! An old enemy in Super Mario World, Big Bully—or just one who looked like him—is now assigned in snow level. From lava to snow? Play the game and you`ll see how things work in 3D.

Cat Bullet Bills
From Tanooki Boos, Tanooki Bullet Bills and Tanooki Goomba from Super Mario 3D Land, and Cat Goom from Nintendo Direct artwork release, here comes Cat Bullet Bills. Can we expect another cat characters in Super Mario 3D World?

Kamek
Kamek made his debut as Magikoopa in Super Mario World 2: Yoshi's Island, and now he's part of Super Mario 3D World.

Super Mario Galaxy Comet Observatory?
Yeah, it looked like the Comet Observatory, a hub from Super Mario Galaxy. When you complete the game, Super Mario 3D Land had special worlds for you. I haven't completed the game yet, but I'd like to be the Comet Observatory. Would you?

So in summary what we have to look forward to is the return of classic characters, the modification (cat versions) of at least a few existing characters, the introduction of at least two new characters, the possible return of the Sunken Ship and other lands from past Mario titles and maybe even the Comet Observatory!