Read the changes listed for version 1.6 first. If your system runs fine, I wouldn't do it. Bios flashes are always a little tricky, and can result in a dead board if something goes wrong. And new bios versions rarely improve overclocking capabilities.
my system is not running fine. im getting choppy audio no matter what card i use (onboard or pci audio) on windows vista and 7. linux and osx are fine. all drivers are up to date. and my bios is up to date for rev 1.1