Diablo III Introducing Challenge Rifts

A post from Blizzard introduces Challenge Rifts, a new way for players to test their skills and gear in Diablo III. They provide this trailer with a look, and offer the following explanation of what sounds a little like duplicate bridge for the action/RPG:
The breadth of build variety in Diablo III is vast, and it can take a lot of time to try them all. Challenge Rifts are a weekly opportunity to try a totally new build, receive a reward for your efforts, and compete with other players on a level playing field!

What Are Challenge Rifts?
Challenge Rifts are a weekly static version of a previously completed Greater Rift. To create a Challenge Rift, we pull a Greater Rift run directly from a player’s account. Once we have that snapshot, we make that exact character, including their items, paragon levels, skills, and gear available for everyone to play.

This also includes an exact copy of the Greater Rift they completed with that character. Enemies, pylons, and the dungeons you encounter will all be exactly as they appeared when the original player completed their run. If you beat the original runner’s time, you’ll be rewarded with a weekly satchel filled with bounty and crafting materials and some Blood Shards.

Challenge Rifts will rotate every Monday, so each week you’ll have something totally new to try.