There were quite a few links in that article. I found this email of particular interest and importance.
+1 There's still far too many people in the tech community who seem to think that WebKit was created from scratch by Apple who just felt like being generous by making it Open Source.
Its a great story ... and marks the beginning of WebKit.
And the end of KHTML. Apple changed WebKit enough that the patches couldn't be merged upstream since kdelibs has to maintain ABI compatibility across minor releases, so it gradually became more unmaintained and less usable. The KDE project couldn't kill it off since other applications relied on it being there, but they couldn't find enough developers to actually keep it working either.