Wrath of the Lich King is boasting many things like new areas, new enemies, new weapons and even new mounts. Here you can see that they are incorporating in a Mammoth Mount, you actually get to ride a giant mammoth around, which is pretty cool.

Even better still is at the end of the video you will see a character on a motorcycle, seems that as part of the engineering skill you will be able to make yourself a motorcycle mount to get around the world. Blizzard knows exactly what to add in to keep you hooked in and grabbing the next expansion.