If you are unsure what Windows Azure is about I have a very good tip for you to get a holistic understand on Azure Cloud Platform without needing to go technically deep.

On an internal Microsoft Conference we had David Chappell as speaker and he really helped the audience understand the topic, really interesting as he is NOT a Microsoft employee.

David Chappell is Principal of Chappell & Associates in San Francisco, California. Through his speaking, writing, and consulting, he helps people around the world understand, use, and make better decisions about new technology.

He has written good whitepapers about this topic I highly encourage you to download and read:
http://www.davidchappell.com/writing/white_papers.php and An Introduction to Windows Azure platform AppFabric for Developers.

Additionally you can find more whitepapers and information on www.windowsazure.com.