Is Skype More Centralized Than Claimed?

From Techdirt - Skype recently suffered a pretty massive outage that prevented, a lot of, if not all, Skype users from logging in. The outage raised certain questions since Skype has been promoted as a decentralized P2P network without a potential central point of failure.

But the truth is Skype was never a completely P2P system as its authentication has always been centralized. In fact, there has been accusations in the past that a previous service by the Skype's founders, Kazaa, wasn't really decentralized either. Moreover, rumors persists that the founders have simply reused Kazaa's underlying code in building Skype. So, just how decentralized is Skype?