At first I thought "how does this improve over consistent hashing?" Then I read it & saw the pretty pictures and realized they address many more concerns that

At first I thought "how does this improve over consistent hashing?" Then I read it & saw the pretty pictures and realized they address many more concerns that just consistent hashing would ... and, even in that case, moving the server list to a single centralized spot (mcrouter) and letting your clients just point at that spot is a definite win. Otherwise, when you update your server list, you have to update every single client. nice work, FB! And well described in the blog post.