[anemecek]

The problem with this argument is that all of the websites that you mentioned were founded before Ror or alternatives were mature enough. Adam D'Angelo (former CTO of Facebook) said that if Facebook was created now, they would not use PHP (source: http://www.facebook.com/note.php?note_id=137376312958147). I can imagine that the situation is similar with the other websites.

[dabent]

The article mentioned he used Python, which is a language I really enjoy working with, but not a framework. Does anyone know what framework D'Angelo is using?

Edit: to note that I used Quora to answer my own question: http://www.quora.com/What-languages-and-frameworks-were-used...