I have been using Linux distributions for a number of years. I certainly don't consider myself a guru of any sort though: Linux is fun but also often very frustrating to use sometimes.
Well it is increasingly popular and available. I use it at work to build numerous servers: files, backup, email, print and at home I have constantly 3 or 4 linux boxes running and even use it on my SonyVaio laptop.
Linux and Open Source gave me back the pleasure of tinkering, of building on a creative substrat that not only allows you to modify and expand but also encourages you to do so.
Today the Linux landscape is has certainly evolved, and big players like IBM, Novel, Sun are invested and investing in getting Linux in the Corporate world to offer an alternative to Windows as a desktop OS.
As I wanted to know more, I practiced and decided that investing in proper training was a good thing.
In 2003 and 2004 I obtained my RedHatCertifications, and I'm currently a trainer and consultant for Oriental Blue consulting Ltd. a company based in Hong Kong specialised in offering Open Source solution to Small and Medium Businesses.