The article mentions the issue of SCO or Novell servers. Virtualisation will not solve that particular problem. They will still be running an ancient OS that no-one 'cept old Bob understands after you've virtualised them. Virtualisation is a hardware solution and as far as ancient servers are concerned it only means you don't have to worry (so much) about sourcing IDE drives or a replacement motherboard that the OS can still run on.
Although I'd still want long odds on someone being able to virtualise a Novell or SCO server in the first place :)
Biting the hand that feeds IT
