Globe and MailZuckerberg's 2012 personal income tax bill: $1.5 billionRegisterIf all goes according to plan, Facebook founder, chairman, and CEO Mark Zuckerberg's share of the profit in his company's upcoming initial public offering will result in him facing a tax bill of around $1.5bn for 2012. What's more, the Financial Times ...Facebook Readies IPO FilingWall Street JournalA sob