According to News.com:
“When Web surfers install the toolbar in their Microsoft Internet Explorer Web browser and click the AutoLink button, Web pages with street addresses suddenly sprout links to Google’s map service by default. Book publishers’ ISBN numbers trigger links to Amazon.com, potentially luring shoppers away from competing book sellers such as BarnesandNoble.com. Vehicle ID licenses spawn links to Carfax.com, while package tracking numbers connect automatically to shippers’ Web sites.”
A similar hyperlinking advertising model named “Intellitext” is already running on several websites (including Designtechnica). While ingenious in theory, the new Google toolbar bypasses a webmasters control of the hyperlinking and puts it into the reader’s hands – with or without their consent by the sounds of it.
Found VIA HardOCP