[tszming]

For a more detailed comparison, see: Is Joyent Really 14X Faster than EC2 and Azure the "Fastest Cloud"? (tl;dr - EC2 isn't that bad) http://blog.cloudharmony.com/2011/11/many-are-skeptical-of-c...

To me, the weakest part of AWS is always on the technical support - you have no right to create a ticket to them unless you pay for the support fee (as contrast to Joyent /Rackspace/Linode), even you have discovered a bug in their system!

On the other hand, I also agree with @latchkey that SmartOS /Ubuntu is an important factor when we are choosing the platform - for a lot of people, ease of use and larger community is more important than cutting edge features like dtrace and zfs.