Amazon AWS team just sent out the announcement on a Windows OS offering for later this fall. This confirms rumors floating around on the AWS Roadmap, and will be a significant boost to the EC2 cloud computing. More here … http://aws.typepad.com/aws/2008/10/coming-soon-ama.html
GoGrid has been offering Windows + SQL Server virtual systems for awhile now. It will be interesting to see price comparisons. I imagine that like GoGrid the AWS Windows will cost more because of the MS license issue. The advantage of GoGrid has also been ease of use, hardware balancing, and nice monitoring tools. On the Amazon side is persistent storage S3 and EBS along with SQS. I’m looking forward to trying it out.
Cloud computing is growing. It is important as a platform for GIS. OGC WPS, WMS, WCS, WMS are making a mark on mapping SAAS and cloud platforms fit this model very well.