Is Ubuntu an Operating System?

Is Ubuntu an operating system? Last week at EuroOSCON, Mark Shuttleworth gave the closing keynote outlining what he believes are the major struggles faced by the open-source/free-software community. During his talk, it became clear that Ubuntu is trying to achieve a radical shift in the software world. Ubuntu isn’t trying to be a platform for mass-market application software: it is trying to be the primary provider of both the operating system and all the application software that a typical user would want to run on his machine. Most Linux distributions are like this, and I think it is a dangerous trend that will stifle innovation and usability, or even worse make the desktop irrelevant.

http://benjamin.smedbergs.us/blog/2006-10-04/is-ubuntu-an-operating-system