This article wanted to make me comment on two issues. 1) Decent abstraction layers ease the moving process. In my current project I was unable to decide on whi

This article wanted to make me comment on two issues. 1) Decent abstraction layers ease the moving process. In my current project I was unable to decide on which datastore system would best cater for the project, so I simply abstracted the datastore enough that I can now (and have) slot in any kind of backend, whether it be BerkeleyDB JE, an RDBMS or a custom in-memory solution. 2) Everyone keeps comparing AWS and App Engine as similar products when they seem to be intended to be quite different by Amazon and Google. Google App Engine provides you a hosted environment in which you develop your app. Amazon's web services work at a much lower level. I'd imagine Amazon's goal is for value added resellers to offer App Engine like services _ontop_ of their stack. That is all.