If you have the latest version of Safari, this program has disabled features. You cannot switch between aqua and brushed metal when you have 1.2.4.
This means that if I set Safari to aqua while using 1.2.3, and then upgraded Safari to the latest version (that has been out for a long time now), there is no way to switch back. So Safari is now stuck in aqua, and because the developer put in a "feature" that cripples the software, I can't switch back.
Moreover, this has happened TWICE! When I upgraded to 1.2.3, the feature was disabled until the developer released an update. Now, I'm waiting for the developer to release another update to support 1.2.4. By the time that happens, 1.3 will probably be out, and I won't be able to change anything back.
So essentially, if you keep your software up to date, you now need to rely on some developer to get around to fixing their software every time you update it. I would be one thing if you had to wait a couple days... but my Safari has been stuck in aqua for MONTHS.