The Oracle of Omaha is back in the news for revealing glimpses of his tax situation. Janet Novack reports:

According to a letter Buffett sent to Rep. Tim Huelskamp (R-Kansas) that the Congressman posted here, the billionaire had adjusted gross income in 2010 of $62,855,038, taxable income of $39,814,784, and a federal income tax bill of$6,923,494. That makes his effective tax rate, as a percentage of AGI, just 11.06%, compared to an average effective rate in 2008 (the most recent year available) of 18.1% of AGI for the 400 taxpayers with the largest incomes, according to figures reported by the Internal Revenue Service.

TOOO must have quite the pile of itemized deductions. He no doubt has a hefty state tax liability in Nebraska. He may have a good chunk of charitable giving. The only other deduction that could be big enough to get his rate down that low would be an investment interest expense deduction -- one that arguably is a cost of doing business for an investor, and which would artificially lower the effective rate on his AGI.

For the record, TOOO's effective rate is much higher when you consider the taxes already paid by the corporations he controls and the inherent erosion of inflation on investment income. It's also worth noting how so much of the income of high-bracket taxpayers is business income from partnerships and S corporations, not capital gains, and increasing taxes on business income is a direct hit on the ability of businesses to expand and grow.

But Warren has his pile already, so it's easy for him to be generous with other people's money.