Change in Management at a Berkshire Unit Encounters Snags - NYTimes.com:
"At NetJets, the returns have been disappointing — and lately the losses severe. Through his investment company, Berkshire Hathaway, he bought the private jet travel business, which caters to the affluent, for $725 million in 1998. Even though Berkshire does not provide detailed results for this small piece of its empire, insiders confirm that Mr. Buffett has yet to recover his investment.
With problems mounting at the unit — heavy losses and allegations of business improprieties — Mr. Buffett...."
The article goes on and introduce David Sokol as both the person that has been assigned to fix things and also a likely replacement to Buffett when the legendary investor eventually steps down.