Billionaire admits to a 'big mistake' in spending $2bn without consulting business partner
Bill Gates once again tops 'Forbes' list as US billionaires' total wealth reaches record high
Downgrade comes after billionaire investor Buffett says he has identified his successor
Buffett now the second richest person on Twitter, behind Bill Gates
Sage of Omaha recently told Bloomberg out banking system 'in best shape in recent memory'
Search giant's shares soar as Apple's sour, despite warm words from Warren Buffett
Annual rich list is based on 'flawed' methods, claims Prince Alwaleed bin Talal (at number 26)
Pundits say Ketchup firm will not be last condiment 82-year-old adds to his investment 'meal'