When did Linux become your primary OS?

I'm very interested to find out what percentage of visitors are new to Linux versus those who have been users for a number of years already. How long have you considered Linux to be your primary OS? If it is not your preferred OS, do you have any plans to switch in the future.

I created a poll investigating this question. Please vote for the range where you began identifying yourself as primarily a Linux user.

The poll can be found here.