 Yes, there's been a little switch not far from the top. Steve Ballmer, now the world's sixth richest person. It's the first time the former Microsoft CEO has been worth more than the company's co-founder and his old boss, surpassing Bill Gates. More than 90% of Ballmer's $157 billion fortune is tied to Microsoft shares, while Gates has diversified his wealth. CNBC's Bertha Coombs. On today's Watchlist...