Jeff Bezos has leapfrogged Bill Gates again for the title of world's richest billionaire. But they're both having a pretty good day. Amazon stock jumped 13.5% on Friday after the company turned in another incredible earnings report -- more than a quarter-billion dollars in profit in three months. Bezos owned nearly 80 million shares in Amazon (AMZN, Tech30) as of August, according to the most recent available data from FactSet. He made more than $10 billion from the one-day stock surge and is now worth well over $90 billion. At the end of trading on Thursday, Gates occupied the top spot in the Bloomberg Billionaires ... (full story)