September 21, 2011; Source: Forbes | Perhaps giving money away brings billionaires good karma. Writing in Forbes’¬†annual issue that lists the nation’s 400 wealthiest people, Kerry Dolan reported yesterday that the biggest wealth gainers this year among the American super-rich are Facebook founder Mark Zuckerberg and hedge-fund tycoon George Soros.

Zuckerberg’s net worth more than doubled from—get this—$6.9 billion to $17.5 billion, the apparent result of Facebook’s private market valuation nearly tripling over the last year. This places Zuckerberg in the top 20 on the Forbes list of richest human beings in the country. Zuckerberg, of course, has been contributing money to education causes—with some bumpy moments along the way. The Chronicle of Philanthropy¬†reports that he gave away $100 million in 2010.

George Soros’ wealth increased by $7.9 billion to $22 billion, a jump that brings him to number 7 on the rich-people list. Actually, though, Soros’ apparent jump in wealth in 2011 is mostly a reporting issue: Forbes¬†says it did not properly recognize all of his assets last year. Soros is reported to have given away $332 million over the last year.

Bill Gates’ wealth increased by $5 billion to bring his net worth to $59 billion, but his friend Warren Buffett’s wealth declined by $6 billion, leaving him with a comparatively paltry $39 billion. Buffett remains at number 2 on the rich list though, so if he writes to ask you if he can serve on your board, I would get back to him.

After all, while he may have been one of the biggest losers of wealth in dollar terms over the last year, Buffett is also, according to Forbes, the nation’s biggest giver, with his 2010 donation of $3.27 billion to the Bill and Melinda Gates Foundation. Over six years Buffett has donated Berkshire Hathaway stock worth almost $10 billion to the Gates Foundation.—Ruth McCambridge