After messing around with many different distros over the last few years, I've come to the conclusion that CentOS is my favorite. I cut my teeth in Linux on Red Hat back when it was free and have always struggled with other Debian based or BSD based ditros because of the differences. As CentOS is basically Red Hat without the invoice, it's nice to come home again. I still have a few Ubuntu boxes around, mostly because Wireless and Media Codecs seem to be better on that platform, but my production stuff is all going to CentOS.
What's you favorite flavor?