One slide mentioned having to fix hardcoded backslashes to forward slashes, and using path.join to make it portable. But on Windows, you can use forward slashes as well at the system call level. You only need to use backslashes on the command line, since many programs interpret a forward slash as the beginning of an argument.
Seeing things like this makes me really happy, even if you are a non gaming linux user, work like this benefits everything else you do and pushes companies like AMD and Nvidia to improve their drivers. I know that since valve started supporting linux a few graphical issues on my fedora laptop have disappeared.
The Mesa improvements mentioned in the slides: <a href="http://www.phoronix.com/scan.php?page=news_item&px=MTY4MjA" rel="nofollow">http://www.phoronix.com/scan.php?page=news_item&px=MTY4MjA</a>
I hope this at least least will motivate more developers to use GL/GLES for game development since it will be easier to keep it multiplatform (iOS, Android, OSX, Linux, Windows). But still there are a lot of things mentioned there that also applies for general big project development on Linux.