The Difference Between Cloud and SaaS
As pointed out on ebizQ, some use the terms “cloud” and “SaaS” interchangeably. As many astute ebizQ readers indicate, there is in fact a significant difference.
ERP Cloud News View
We believe (like many others commenting on ebizQ) that SaaS is a delivery model, and that the cloud makes SaaS possible. However, SaaS is not and we do not think it can become the cloud. The reason is simple – the cloud extends beyond SaaS and external clouds into private cloud areas. In an ideal world all resources (both private and public) can be used and exchanged according to business needs. We believe the cloud frees up the user (an end user or a software developer) from its own limited resources or the proprietary resources of a SaaS vendor.

Nonsense – a private cloud is just a dta centre outsourcing.