so if we say the 18 million are 5% of the sold systems and lets say today its 9million (8-10 million) it would be the half so even preinstalled desktop-systems are at 2,5% and I think we can agree that more more of the 97,5% of the rest of the market mostly windows but also freedos users have switched to linux than from the 2,5% switched back to windows. It is a very high change that I am right here. So my 2-5% is very realistic if not a conservative guess.
Kenyon said in his talk that Ubuntu was shipped pre-installed on eight to ten million computers worldwide last year. Canonical expects this to increase to eighteen million next year, which they calculate to be five per cent of the total market.