Quoting from TechWorld

Virtualisation technology is the current darling of the software business, data centre managers and financial directors alike. Everyone likes its ease of deployment, maintenance, and usage -- but above all, they like the money it saves. The problem is though, how to quantify how much you've just saved.

Doing more with less has been the mantra of most businesses of any size ever since the Y2K debacle. Having to replace all those systems, sometimes from top to bottom simply because it was impossible to know whether or when a Y2K bug might strike, was hugely expensive.

The Y2K Cassandras were by and large heeded by enterprises, despite dissenting voices -- including that of the labs-test based magazine on which this author worked at the time, which argued that little evidence could be found that the problem would in practice generate big issues.

But what resulted was the adoption by most enterprises of a solid, business-based attitude to IT that negated the snake-oil charms of salesmen promising technologies and fixes for coping with the humungous burst of online traffic that, for many, never came.

As a result, IT managers have had to work a lot harder at getting more out of the technology they already possessed rather than fixing under-capacity by bolting new, untried stuff onto existing kit.

Virtualisation is key

Virtualisation is proving to be a key technology in that drive to extract maximum benefit from today's pretty potent hardware. Stories abound of organisations in both private and public sectors who, through virtualisation, have been able to cut the number of physical servers by a factor of five or more. Consequently, remaining systems work nearer their full capacity.

But a problem remains. It's not so much that an organisation needs to cost-justify the purchase of the software -- though that undoubtedly helps. It's more how to charge the cost of providing the service, now underpinned by virtual rather than physical machines, back to users.

Read the rest of the article, here.