Jack Schofield asked Jakob Nielson what is holding up progress on the web? Nielsen responded with three things:

Evil Design

"Google has made billions by putting the ads where people do want them, rather than where they don't want them."

That is an excellent point.

Jakob Nielsen has recently published an article titled: Mental Models For Search Are Getting Firmer. The article basically states that if your sites search functionality behaves different from Google, that users will get confused.