The letter will be posted on Berkshire's website along with its 2008 annual report and fourth quarter earnings.
Buffett's shareholder letters are always a must-read for many investors, and Berkshire's tough year is increasing the anticipation even more this time around.
The stock is down over 47 percent from the all-time high of almost $150,000 back in December of 2007, and recently fell to a five-year low.
Many of the stocks in Berkshire's portfolio have been battered, especially the financials. Berkshire's big derivatives contracts are losing billions of dollars on paper as stock indexes continue to fall.
Several of Berkshire's operating companies depend on consumers, so they're suffering along with the economy. And it was a tough hurricane season last year, which doesn't help Berkshire's insurance businesses.
CNBC's Jim Cramer has accused Buffett of hypocritically "selling America" and the outspoken Doug Kass predicts Berkshire's investors will abandon Buffett as the stock continues to fall over the long-term.
So, writes Reuter's Jonathan Stempel, "Warren Buffett has some explaining to do."
Morningstar analyst Bill Bergman tells Reuters, "It will be interesting to see if Buffett himself has learned lessons he might not have learned in his long career."
It's also possible, of course, that Buffett will write that while things don't look good now, he's taking advantage of the tough times to make deals that will add to Berkshire's long-term profitability.
Bloomberg's Erik Holm points out that Berkshire may "report its worst results since Warren Buffett took over in 1965," based on a metric that Buffett himself regularly cites: book value per share.
Gary Ransom, an analyst with Fox-Pitt Kelton Cochran Caronia Waller, estimates for Bloomberg that the measure of assets minus liabilities fell 8.5 percent last year for Berkshire.
There's only been one annual drop in the past. Book value per share fell 6.2 percent in 2001.
The two analysts who provide earnings forecasts for Berkshire expect the company to report fourth quarter operating earnings of $1486.50 a share. That would be a drop of 2.1 percent from 2007's fourth quarter.
Warren Buffett Watch will be up bright and early tomorrow morning with full coverage.
Current Berkshire stock prices:
Class A: [US;BRK.A 78600.0 250.00 (+0.32%) ]
Class B: [US;BRK.B 2564.0 --- UNCH (0) ]
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Pilgrimage to Warren Buffett's Omaha: A Hedge Fund Manager's Dispatches from Inside the Berkshire Hathaway Annual Meeting by Jeff Matthews
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