I have done both building your own data center and running the whole enterprise on AWS. I like AWS better. Some folks have hinted at it here but the ability t

I have done both building your own data center and running the whole enterprise on AWS. I like AWS better. Some folks have hinted at it here but the ability to spin up a node rapidly is a huge game changer. Ya, you could accomplish some of this with open source and your own hardware but the flexibility will pale in comparison to what you get from Amazon. A year ago, I was all on board the OpenStack train. I think it is great by way of keeping Amazon honest and therefore keeping prices in check. I'd still pay a premium for Amazon over a public OpenStack or a roll-your-own solution.