Julie – no deliberate oversight. My thoughts on each color: yellow elicits a warming effect; purple evokes royalty; black means strength and authority and white dignifies purity. These four are powerful colors to use on a website.

White and black are so basic, it’s hard to find a website not using both. But purple and yellow are challenging — different shades mean very different things (think mustard-yellow vs. bright yellow or light purple vs. very dark purple).

Dramatic changes like you mention would only create, as Ruud says, online drama. And probably not the good kind.

The only company I can think of that changed their logo’s colors, and went on to incredible success, was Apple.

Changing colors, logo’s, layouts — changing anything that means something to others in the relation carries with it a risk.

I like Google’s way of doing it: slowly but surely change things. A bit here, a bit there.

Complete, dramatic overhauls are very good to make a big SPLASH and have press and community talk about you 🙂 It’s online drama 🙂

For instance, changing the blue color on facebook to green or YouTube to blue ..