The question of weather SaaS is Cloud Computing keeps coming up again and again. So, since I didn't get to attend that session at Cloud Camp SF I'll weigh in here.

I view cloud computing as a commercialized extension to utility/grid computing from government and educational spaces. My definition of cloud computing is, "cloud computing is a commercial extension of utility computing that enables scalable, elastic, highly available deployment of software applications while minimizing the level of detailed interaction with the underlying technology stack itself."

More details in this article (mine):
http://www.productionscale.com/home/2008/4/24/cloud-computing-get-your-head-in-the-clouds.html

In that definition you can see that I'm positing that SaaS is enabled by Cloud Computing. SaaS is the "software application" that is enabled and endowed with all those awesome attributes provided by Cloud Computing. That makes most SaaS offerings Cloud Computing Applications as opposed to traditional stand alone or even web applications. It does not make the applications themselves Cloud Computing.

The most interesting thing about Cloud Computing to me is that it enables entirely new types of business to exist and be economically viable that never could have persisted before. The economics changed and this is only the tip of the iceburg. Fun times!