Will corporate America use SaaS components?

Build the App from scratch - Expensive to build, expensive to maintain, job security for the author, bound to be riddled with bugs until version 3 at least, and worst of all given my deadline, it takes a long time (think of an estimate and multiply by 3)

Download some open source code form SourceForge - The Mega Corp USA will still be responsible for maintaining the code in the long run (Expensive), I need to customize the open source code to my requirements, but at least I have a running start which should reduce the time to delivery.

Can Web Services & SaaS be used to replace Client Service applications?

Obviously web services are just that - services. Therefore this may seem like a ridiculous question.

However, I don’t think it is. After all, an application is simply multiple modules communicating with each other via procedure / method / function calls.