Now a new generation of inheritors has risen to take their place atop Bloomberg's just-released list of the world's richest families. The Walton family, heirs of Walmart founder Sam Walton, bring home the gold with $238.2 billion. The Mars family, descendants of secretive Forrest Mars, bring home the silver with $141.9 billion. (Folks sure do eat a lot of M&Ms.) Finally, the Koch family brings home the bronze with $124.4 billion. (Kind of fascinating how the money gets made in cities like Bentonville and Wichita before getting squandered in places like New York City, right?)