Streamingmedia.com have published a great tutorial and overview on how to get started with Amazon's new Cloudfront Streaming service. While the service currently only supports on-demand streaming of Flash video content the company also has plans to support live streaming in the near future. This service looks like a very cost effective and scalable video streaming service, and is relatively easy to set up.

If you are interested in this service and require any help or advice then please feel free to get in touch. I've set up several video streaming environments on Amazon Cloudfront as well as EC2 in the past.