Notes:
Lets face it: Linux/BSD/Unix today are completelly unintegrated.
Why ?
Because the soul or personality of a software are in its configuration files. Softwares, as people, should have affairs, integration, through their personality.
Open Source nature is to produce islands of projects: each one follows its own rules. So we have many config files format, APIs, and no unified namespace.
So a lot of ad-hoc integration must be done in the packaging time. This leads to different Linux distros to have different feels.