According to the Economist magazine:

First, interest rates have come down from their astronomic levels five years ago.

Two, steps have been taken to improve the way Brazilian companies are monitored for corporate governance. This is particularly important for the protection of small investors.

Three, the government has been managing the economy well.

Four, there is a commodities boom.

Five, Warren Buffet has been purchasing the Brazilian currency.

Source: The Economist Magazine, October 25th 2007