I just updated my ASUS P6T rig to OS X 10.6.3 with the built-in online Software Update application without any problems. It comes with a new Darwin kernel which has the number 10.3.0.
I also installed a brand new Intel X-25 M G2 solid state disk (SSD) and boy, this setup is starting to fly. Boot time from the grey apple logo to the login window is just 11 seconds! Applications like Mail or Safari start instantly, it’s like clicking an application icon and BOOM the software is on the screen. Even Photoshop CS4 with the default plugins enabled starts in less than 4 seconds. The performance increase is awesome. Forget about buying that slightly faster CPU… pour your hard earned money into a fast SSD. The only downside is that OS X still lacks support for the TRIM command for SSDs. It’s already available in Windows 7 and even in Linux… but unfortunately not OS X. Considering that Apple already ships its own notebooks with (overpriced) optional SSDs for quite some time that’s certainly a bit lame.
Because disk space in the SSD is usually pretty limited, I instructed OS X to put my home folder on a normal hard disk drive. Only the operating system itself and all applications are installed on the SSD. I have quite a bunch of stuff installed on my 80 GB Intel SSD but still got 65 GB left. To use a different home folder you have to right-click the account name in the Accounts preferences window and enter a different home folder location.