WARNING!!
Suppose you only use Linux, updating the firmware to ProTune version has one tricky part. You can’t downgrade to old firmware without CineForm Studio. Manual firmware update probably bricks GoPro HD2 which I had experienced yesterday. The camera would stop working.
I had to use a Windows laptop to fix the bricked GoPro camera which costed me few hours. I followed the video instruction.
The video quality of ProTune firmware likely produces white washed which needs to be enhanced by CineForm Studio. I tested CineForm in Windows XP guest OS and it was almost useless.
http://alex263.wordpress.com/2012/03/25/update-the-firmware-without-cineform-studio/
Freedom, World peace in unity! 