The current production release of FreeSWITCH™ is version 1.4 created from tag 1.4.6 on 3 June, 2014. This is the recommended version to install for production systems.
Pick Your Poison
The core developer team will only entertain bug reports on the latest Master branch code—it is impossible to debug old code that has long since changed and might have been patched already.
On this page you will find general information that applies to all installations of FreeSWITCH. Follow the links to your target operating system for specifics. The development team uses and builds against Debian, although other linux variants are supported. They recommend Debian because of its stable, yet updated, kernel and wide support.
If you're new to FreeSWITCH™ consider purchasing the FreeSWITCH™ book and be sure to read this introductory article: http://www.linuxpromagazine.com/Issues/2009/106/TALK-SOFT.