Alright... So APC has been pretty unstable for me on 2 separate servers running PHP 5.3.x and PHP 5.4.x. So I figured I'd give XCache a try after reading about similar problems with APC.
Here's how to install XCache 3.X from source on CentOS
Get the latest version of XCache from here: http://xcache.lighttpd.net/#Downloads
Latest version at the time of this writing is XCache 3.0.1