I started out trying to use CentOS before switching to F15 after I decided that manually compiling every component and half of the compilers to get pretty much any of the miners working wasn't worth the hassle and was going to lead to a broken installation anyway.  Fortunately, I'm not trying to do anything else with the machine I am running Linux on at the moment, but anyone who is mining on the side might have good reasons to run CentOS.