Cloud computing and SaaS - the IT world is on the cusp of a revolution. There have been enough Blogs on where these changes will take us. But I would like to push the thinking a little further.
A caricature of the SaaS and Cloud premise is that the world is moving from an "on premse" to "off premise" service delivery model. With the ubiquitous network, commodity operational practices an "off premise" model promises economies of scale that are unavailable to any one IT group. SaaS is a natural from Service Oriented point of view. Most SaaS vendors aim to provide expose their applications as web services.
The first difficulty with SaaS is not that applications expose their themselves as services - rather how do you orchestrate these services into business processes - the business processes that help a business differentiate - do business better. Without this orchestration there is no real SOA and we return to the days when applications where stove piped and IT was not strategic. How Moicrosoft, Oracle and IBM address this will define the next generation of IT. I fully expect IBM and Microsoft to provide an answer that allows independant SaaS providers to thrive. I would expect Oracle will go to the "Suite as a Service" as its major strategy - where integration is deep inside their "cloud" - far from the businesses that use their services - the antithesis of strategic IT.
One last thought - SaaS orchestraton cannot be based on the idea that off- and on- premise are absolutes. I am sure both the cloud will have no real boundaries - my PC and its software will be just as much a part of the cloud as the systems installed in the huge data centers. Services and processes wll have no real boundaries - SaaS Orchestration won't either.