I am a recent convert to Ubuntu from all things Windoze. I have always been a Linux fan but too scared to make the jump. However, we recently decided to build a Asterisk pbx system at work and that gave me just the excuse I needed to jump in with all fours.
I have settled on Ubuntu as my system of choice and use it almost exclusively. Haven't booted any of my machines into Windoze in over three months.
Still learning though...a lot I still don't know.