I've tried it (a few times) but do not (currently) use it regularly. I plan to buy another hard disk for this laptop when I have some free time, and have a more serious play with Linux, probably PCLinuxOS or Ubuntu/Kubuntu. The main problem is still the lack of alternatives for some of the Windows apps I use regularly - in particular a decent PDF editor equivalent to Adobe Acrobat Professional. Wine is still not the solution in all cases, and running Windows in VMware is defeating the point of running Linux!
I use it regularly. I'm definitely no expert at it, but I get by. I had a friend install it on my laptop around a year ago, and I've been using it ever since. I have both Xubuntu and Windows XP installed, but I primarily use Xubuntu. I also have a used computer running Ubuntu Server (aka. it just has a text terminal, no GUI or graphics whatsoever).
I used ubuntu for about a year, recently switched over to slackware (which is giving some headaches). I'm getting pretty comfortable with all the really linux-y stuff, like the command line and editing config files.
