Thank you very much, I was looking for some questions like that.

I see, in fact it is not a pratical question. Anyway I think most of these questions are made because Ubuntu users really want to try the new features but don't want to give up stability. Others have doubts about the new unified Unity. I recently got informed that new Unity makes use of CPU to work on machines without 3D support. This makes Ubuntu sluggish. That topic should be better explained on Ubuntu homepage, where we can't find minimum requirements, so people with no 3D support should be aware that perhaps they shouldn't upgrade (if it is to install another DE, what's the point really).