Ravines

Ravines are a new natural structure coming to 1.8, announced by Notch on June 22, 2011. Ravines are tall, long structures, about 5-20 blocks in height and variably long. The width is barely a few blocks, usually no more than 5, sometimes making ravines hard to navigate from below. Ravines can be both above and below ground, and can connect to caves and dungeons. Because of their large surface area, ravines frequently have lava, or water flowing into them. Ravines may also have small ledges along the top, possible to travel along. Ravines can be found at any level. Those above ground are also called "Canyons."

During the QA session at PAX, a ravine was captured in fairly good detail on Fdoke's Livestream. (at 24:00 in)

An underground Ravine: