See the following, an interview of Mark Shuttleworth about ubuntu,

http://www.guardian.co.uk/technology/2008/may/22/internet.software

I like this, because that's the truth:

TG: Do you think that GNU/Linux will ever become a significant force
on the desktop?

MS I think that depends on how people define a desktop. If people
continue to define a desktop as the thing that they run Microsoft Word
on, then Windows will retain its position. My sense, though, is that
people are increasingly defining the desktop as the thing that they
get access to the internet from. In that case, there's a real
possibility that we're able to shift people onto different platforms.
I think it's the emergence of the internet as the killer application,
the thing that describes what you want from the computer, that opens
the door to us.

Enjoy