One of the Oracle of Omaha's favorite stocks to buy is Berkshire Hathaway's new leading provider of dividend income.If you've ever wondered why professional and everyday investors pay such close attention to what stocks Berkshire Hathaway (BRK.A -0.54%) (BRK.B -0.72%) CEO Warren Buffett is buying and selling, look no further than his track record. Since taking over as CEO in the mid-1960s, he's presided over an aggregate return in his company's Class A shares of almost 5,470,000%, as of the closing bell on ...