I found this Wired article very informative and enlightening on the Cloud Computing or Software-as-a-Service (SaaS) or Hardware-as-a-Service (HaaS) ecosystem. I personally believe we are quickly moving to an online world of services where business decision makers can select, mix-and-match (mashup) and competitively bid for interactive marketing services instead of technologies. This will also alleviate the need to internally invest in large infrastructure projects that require extensive levels of reviews, approvals and capital.
I am a strong believer in these services and feel that Amazon, Google, Microsoft and others will offer an array of services that open this market up over the next couple of years.
My personal experience with interactive services started when I was at Dell in 1998-1999 where we were developing systems management services. I then worked on managed web services at Intel Online Services (an attempt by Intel to extend its brand into services and gain an understanding into why Sun Microsystems was very successful, at the time, in the web server business). Both programs were very early, maybe too early, but were exactly where the market is heading today. The first company to be truly successful in this area was and is Salesforce.com.