John Gruber has come up with a concise posting onInterface Details: iTunes vs. Safari. Some excellent points. Some I noticed, some I never in a million years would have.
In a nutshell, without ruining the surprise, here are the detals. Two-color scheme (Graphite and Aqua), Click-through buttons, Fast Window Resizing, and Search Box Labeling.
Nice stuff. Well-thought out and well presented.