Please read this report from a couple months ago.
Brazil Sugar Ethanol Update – February 2006, USDA Foreign Agricultural Service"
It reports that ethanol accounts for approximately 15% of the fuel used in Brazil. A higher percentage if you only consider passenger cars.
What Brazil has done that made the biggest difference in the last decade was start producing much more of its petroleum resources. If you will look at the following link, you will see how they quit needing foreign oil.
Got it. A brilliant move on their part.