For small businesses, the significance of this primarily comes down to cost. In many cases, using cloud-based infrastructure is cheaper than running and maintaining one's own physical servers.
Likewise, says Read Write Web, the pay-as-you-go licensing model of software-as-a-service providers provides lower costs than traditional software, or at least distributes that cost across low monthly payments.
Have you switched from a desktop app to a cloud-based app? Are you finding savings by switching to cloud apps?