Cloud help control costs
"our customers were demanding cloud and cloud is seen as a good way to cut physical footprint and help control costs"
What kind of business needs several thousands servers. Sounds like a serious case of over design. Or more likely a bad design that someone keeps throwing servers at. I suspect your customers aren't really demanding the cloud and moving to the cloud won't really save money. I mean you'll still have to pay for your licenses for your virtual servers in the cloud.
Go on, convince me otherwise, show me a fully worked out example of a company moving to the 'cloud' and saving money.