An example of how Minecraft could look like with Texture Packs or Mash-up Packs.
Earlier today, 4J Studios have announced that they will soon be bringing full-on customization packs to Minecraft: Xbox 360 Edition. These packs will "make Minecraft look like a different game," according to 4J Studios.
Different from the already announced texture pack support, which will be included in their next Title Update, the so-called "Mash-up Packs" will allow players to download an entire new skin for Minecraft. This includes a texture pack, skin pack, custom designed user interface, music and custom themed world. This allows 4J Studios to provide a full adventure experience, depending on how they make use of this new feature. You could be expecting custom survival maps with custom textures, music and everything just customized to that particular map.
Which Mash-up Packs will be available, when they will be available and how much they will cost is unknown at this moment. Mash-up Packs and Texture Packs will be available soon after the launch of Title Update 12. Don't expect it all to be available on the same day as the Title Update launches though - it may take some time for 4J Studios to create the Mash-up Packs and Texture Packs.
Title Update 12 is still being bug tested as of the 25th of July, so it will likely not be available until early August. The update has yet to enter Microsoft Certification, which could take up to a couple of weeks. Expect it to be out in early August.