Bryan,
I use Fedora (still FC3) at home, and CentOS/RHEL at work.
Setup is more or less the same, using Komodo under KDE (except that at work my desktop runs WinXP and I use an X session under cygwin on the linux machine). Can't really remember if I had much problems setting things up. When using linux, you bump into issues once in a while. But when using windows, issues arise too (recently had to setup an IIS6, you can't believe the things I bumped into, felt like crying a few times). Generally, I find it easier to google a solution when a linux issue arises compared to a windows problem.
For Rails development I use 4 KDE desktops, which can be reached with a
keyboard shortcut. I have separate desktops for komodo, firefox, tail -f
of development.log, and webrick. Except when really needing to click
something in firefox, I only need to use the keyboard (I'd prefer 4
monitors though 
My switch to linux was a learning experience that also enabled me to
switch jobs (from being a mfc/vc++ programmer for ages) to a more
versatile (I also get to do Rails development sysadmin related job.
I *might* try Mac OSX in the future, but there's slight chance I'll return to windows. (if I'd document all the issues I bumped into when getting that IIS6 to work, I think it would make anyone think twice about installing it)
Piet.