Scott Watermasysk has a great high-level comparison of the cloud computing offerings from Amazon, Google and Microsoft in his post Cloud Options - Amazon, Google, & Microsoft. Below are some excerpts from his review
Amazon (AWS) Most mature offering of the three. Google (AppEngine) I get the sense that Google is trying to appeal to a small and focused audience (well, as small as Google can). There is nothing wrong with this approach, but I think long term I would feel handcuffed on their platform. Microsoft (Windows Azure) Microsoft still has a lot of "execution" to complete, but overall I am thoroughly impressed with the total breadth of their offering.
If you are interested in this space you should read Scott's entire post. I was thinking of doing a similar comparison but Scott's post hits the highs and lows of each service. I completely agree with his analysis, Amazon provides a mature offering but I balk at the complexity of managing and deploying my own VM images. Google's offering seems incomplete and it is bothersome that they do not provide any Web services (SOAP or REST). Microsoft has an ambitious offering which combines the ease of use of Google's offering with a more complete set of services but the proof will be in the pudding since it isn't yet broadly available.
This is an excellent review by Scott Watermasysk and is definitely worth sharing.
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