[calufa]

I use rackspace and its very cool. Rackspace is fast and simple, and is also cheap. Their server runs fast, and smoothly. AWS is sometimes too complicated, lots of config, lots of choices, lots of weird price changes -- I am talk about the recent spot instances weird pricing fluctuations, and other wierd episodes they have had. Unless you know exactly what you are doing scaling in AWS will take more time and effort -- Unless you are Zynga, and you need a stupid amount of server which almost noone of the server providers except amazon have, or you dont want to deal with relational db scaling problems, or other of the expensive and specific service that amazon offers I dont see why complicate things in the "building stage". AWS is too complex for my use cases, and my software is usually transparent to the server where he is running, so I can always port my code. Rackspace API is stable and it talks JSON, which is cool because my frontend and backend talks javascript.

I guess this question is too open... the answer will always be, depends on what you are building..., and you amount of experience on the field... In my case several 8gb rackspace servers with a cost of 10 dollars a day seems to work well for collecting and crunching gigabytes of data.

[gdgdgxdd]

I'd be keen on rackspace if there were a way to painlessly scale instances of an app without being an admin.

Heroku covers this very well.

[calufa]

Provisioning is not that hard, nor scaling -- you can always create a image and create servers from that image. In my case, I usually create a server that listens to git and the rest is synced by some program who is also listening the folder where the git repo is.

Heroku looks cool, but I am used to compile things...