I agree it is good in theory but it still has a long way to go, I used it for content delivery rather than a full build, the data served wasn't amazingly fast, infact it was just as fast as when it was placed on a shared lightspeed server, although obviously this would not be that case during traffic spikes.
However there are issues regarding leeching and hotlinking that amazon (last time I looked) hadn't provided a solution for (although there are third party solutions out there) and the interface and account management is far from user friendly which is nuts.
With that said it does provide a good, cheap solution or so I thought before the outage and data loss issues. It now seems it is not all it boasts to be, I certainly wouldn't structure my main frame around it just yet, but still worth using for content delivery and streaming that is not of huge value if hacked.