So What is Cloud Computing ?
"Cloud computing is Internet-based ("cloud") development and use of computer technology ("computing"). The cloud is a metaphor for the Internet, based on how it is depicted in computer network diagrams, and is an abstraction for the complex infrastructure it conceals."Live Services, Live Mesh, Live Platform, Windows Azure, SQL Services, .Net Services . . .
these are some of the titles associated with the cloud offerings from Microsoft.
So where should we start from ?
I would recommend to start with the Live Framework. Here is a brief description of some of the basic concepts of live framework including some of the common application models and different flavors of Live Operating Environments available today. ( What is Live Framework and Why Should I Care? )
( Mike Taulty has written some good posts describing his development experience with Live Framework SDK which might be useful for all. )
The next step could be to explore the Azure Services Platform, which includes .Net Services, SQL Services, SharePoint Services and Live Services as well.
( Here is a good list of Links and Resources from Sriram Krishnan on Windows Azure. )