Let me propose a use case, and I would appreciate if you indicated if I'm totally off base.

A virtual world, where actors(users) interact with each other, with the cluster providing validation and consistency between actors over a dynamic geography, where each node in the cluster would be handling the realtime requests of actors that are capable of interacting with each other, distant actors would be on different nodes.

(Would this work for a distributed server infrastructure to say an large online game?)