I have been trying to use Compiz and i had two different results. At the first trial, it was a mess. No titlebar on every application, too much error/warning messages on the console, and many problems. I stopped using compiz then (besides, it's just a cool effect. It won't make my salary increased ).
At the second trial, it was very nice, as Compiz is getting mature and other components as well. Right now, i'm enabling compiz on both my laptop and desktop and i never had problems with it. Too bad, Slackware do not include ccsm (Compiz Setting Manager), so i had to install it using SlackBuilds script from SlackBuilds Project (they have provided all the required packages along with the build steps). I tried the application, but it seems that it won't save the configuration
Well, cool desktop effects can be one simple promotion to attact people to use Linux. If you can do the nice effects without having to buy expensive hardware, what would you do? I'm sure many people who have tried to use Vista will be impressed by what Compiz/Compiz-Fusion can do with not so state-of-the-art hardware.