Google and Usability

Google doesn't just practice agile product development. The product management emphasizes users and usability in a variety of ways:

• Test marketing - Put early versions of the product in front of prospective customers and internal employees to determine and improve the usability and usefulness.
• Humility - Solicit ideas from anyone and everyone; don't assume you already have the answers.
• Observation - Examine what users actually do, whether the terminology in the product is understandable, and how efficient the user experience is.
• Defer other considerations - Worry about helping the user first, and how to profit from it later.

I'm not sure if I agree with the last approach. While it's to some extent true that you can usually find a way to profit from an extremely popular product (such as by placing ads on it), Google seems to have been somewhat lucky in this regard. With all of the products Google has developed - Gmail, Local, Groups, etc. - has any of them yielded income significant relative to what Google gets from Google AdWords on its search page and other people's sites?