OSX, since 10.6, has a built in screen recorder inside of QuickTime. Admittedly, QuickTime sucks and YouTube has other preferences, but it gets the job done if you need a free tool to record your screen.
There appears to be a bug with Chrome 22 on OSX 10.8.1 where using
webkit transitions causes text to look disgusting when the background is faded in and out.
Hopefully, this gets fixed sooner rather than later. It looks horrible.
It is definitely a Chrome bug — the problem is not exhibited in Safari.