In Europe and Australia, Nintendo are offering a free Xenoblade Home Menu theme for the Nintendo 3DS with Xenoblade Chronicles 3D.
In Europe, you’ll need to purchase the game via the Nintendo eShop before April 9th to get the theme for free. Meanwhile, in Australia and New Zealand, you can get the theme by pre-ordering the game at these retailers.
Additionally, Europe and Australia are also getting the Xenoblade faceplates for the New Nintendo 3DS. These are available as part of a Xenoblade or New Nintendo 3DS/Xenoblade bundle in the U.K., while in Australia they’re exclusive to EB Games.
Nintendo have not yet announced if or how the theme will be made available in North America.