Google's platform

Interesting speculation on the architecture behind Google's GMail.

"It's a distributed computing platform that can manage web-scale datasets on 100,000 node server clusters. It includes a petabyte, distributed, fault tolerant filesystem, distributed RPC code, probably network shared memory and process migration. And a datacenter management system which lets a handful of ops engineers effectively run 100,000 servers."

Can it be true? It's the holy grail of distributed computing. And Google has already built it?