This post was published more than a few years ago (on 2007-07-16) and may contain inaccurate technical information, outmoded thoughts, or cringe takes. Proceed at your own risk.
If, like me, you were foolish enough to install the Safari 3 beta, and are now wondering why the heck RubyCocoa won't work (or worse yet, why the install keeps failing), check out the article Safari 2, Safari 3, Adium & forcing WebKit Frameworks from SubtleGradient.com. Once I went through the steps outlined here, things worked fine, where the Safari 3 Beta Uninstaller had not. (The beta Uninstaller didn't properly restore the old version of WebKit, plus somehow wiped out my entire WebKit Headers folder.)