While there's always an element of 'he would say that, wouldn't he?' when vendor executives speak, Mr Clayville (pictured above) pointed to large-scale adoptions of Amazon Web Services by Suncorp and the Commonwealth Bank.
The latter has halved its storage costs by using AWS, he said, and expects to save hundreds of millions of dollars.
"There's a sense of urgency" as organisations realise the importance of cloud technology, he said.
Execution-only stockbroker Open Markets CEO Rick Klink said his business would not be possible without cloud systems, as it relies heavily on being able to pay for as much compute power as needed at a given time rather than making an massive capital investment to cope with peak loads.
Trading volumes are highly variable, so "we need to allow for black swan days," he said, and as the ASX is only open for one-third of the day "we only turn them [the systems] on when we need them."
Similarly, NAB is using AWS for its main website, as well as those of subsidiaries UBank and MLC.
"The digital expectation is 'always on'," said head of digital and online channel services David Bird (below), and AWS combined with automated provisioning and change management allows the bank to provide the availability and responsiveness customers expect - even on the three peak days of the year - along with the ability to roll out many small changes.
With AWS, NAB can run at "internet speed," he said.
Mr Clayville noted that while security - or rather a lack of it - is sometimes put forward as a reason for avoiding the cloud, he recently met with a group of bank CIOs in London, and they decided AWS is probably more secure and provides better availability than their own data centres.
Disclosure: The writer holds NAB shares.