Rank: 2 (Previous rank: 1)
CEO: Rex W. Tillerson
The oil giant made a big bet on the domestic natural gas market late last year buying Texas-based XTO Energy for $41 billion. But refining and exploration remain its backbone. The company drilled 45 new wells last year and hit pay dirt on nearly two-thirds of them.
Other big projects: new ventures in Qatar, the Black Sea, and Kazakhstan, including the giant Kashagan field located offshore in the Caspian Sea. With operations in nearly every corner of the planet, Exxon always seems to get a seat at the table when big projects arise. Maybe size does matter. --Peter Newcomb

3. Chevron
Rank: 3 (Previous rank: 3)
CEO: John S. Watson
With prices for crude oil and natural gas off sharply from their recent highs, revenue at the oil giant tumbled 37%, from $265 billion to $167 billion. The good news: Production of oil and gas jumped 7%, thanks in part to a 57% success rate on its exploratory drilling.
But another pitfall looms: Chevron has a heavy exposure to high-acid crude, particularly its deep-water projects in the U.K. If the government forces it to start processing the high-cost oil, Chevron may opt to cede its drilling rights, a move that would result in a sizeable charge against earnings. --P.N.

Rank: 4 (Previous rank: 5)
CEO: Jeffrey R. Immelt
The house that Jack built ended 2009 by selling a controlling stake in its NBC Universal entertainment unit to Comcast, a deal that valued the new entity at $37 billion. Investors largely shrugged off the deal, but as concerns over its finance unit begin to fade -- and talk of a dividend increase start to heat up -- GE stock lately has been on a tear.
GE chief Jeffrey Immelt hopes to keep the momentum going. He's investing $6 billion to develop new medical products and technologies, and is making big bets on green technologies, from fuel-efficient turbines to "thin film" solar panels. --P.N.

Rank: 5 (Previous rank: 11)
CEO: Brian T. Moynihan
Say this about Bank of America chief Brian Moynihan: He certainly knows how to talk the talk. In his letter to shareholders, Moynihan went out of his way to thank U.S. taxpayers for making $45 billion in TARP funds available. He also described how he is working closely with "policy leaders" on financial reform.
Whether he can walk the walk -- i.e., turn around BofA's fortunes -- is another matter. While the company did repay its TARP loan in December, it is still sitting on billions of dollars of vulnerable residential and commercial mortgage debt -- one reason the company spent 8,000 words discussing risk in its annual report. --P.N.

Rank: 6 (Previous rank: 4)
CEO: James J. Mulva
When Warren Buffett said he was "dead wrong" to invest in ConocoPhillips, Conoco chief James Mulva must have taken note. The Texas-based oil company -- the nation's third largest -- has been going to great lengths trying to shore up its balance sheet by selling assets, reducing debt, and reining in capital spending.
In March, Conoco said it would sell half of its 20% stake in Lukoil, a move that could raise $5 billion. Other potential sales: the company's 9% stake in its oil sands venture Syncrude and its 50% ownership in the Flying J truck stop chain. --P.N.

Rank: 7 (Previous rank: 8)
CEO: Randall L. Stephenson
Ahh, the glamorous life of AT&T: best friends with Steve Jobs, exclusive rights to the iPhone (for now) and carrier of choice on the iPad. So why, with everything going for it, did the stock miss a huge rally? In the year ending April 1, Apple soared 109% and the S&P 500 rose 41%. AT&T? Down 2%.
The problem is growth, or lack thereof: little in its saturated wireless business and a decline in landlines, which still accounts for 25% of sales. Unless its high-speed Internet business takes off or the iPad drives new wireless growth, the beatings by Wall Street will continue. --Michael Copeland

Rank: 8 (Previous rank: 7)
CEO: Alan R. Mulally
In March, Ford completed its exit from the luxury car market by selling Volvo to China's Geely Automobile for $1.6 billion. Although the sale represents a sharp loss -- the company paid $6 billion for the Swedish automaker eleven years ago -- Ford posted an annual profit of $2.7 billion in 2009, its first profitable year since 2005.
Assisted by the "Cash for Clunkers" program (not to mention Toyota's accelerator woes), Ford recaptured its position as the nation's largest carmaker in February. Which is why Ford's CEO Alan Mulally can now look abroad, including big markets like India, where it recently introduced the compact Figo. --P.N.

Rank: 9 (Previous rank: 16)
CEO: James Dimon
CEO Jamie Dimon, who's been hailed as one of the banking industry's top leaders, called J.P. Morgan's annual results "mediocre." The industry must beg to differ. J.P. Morgan's revenue jumped in 2009 and profits more than doubled.
It's the latest proof that J.P. Morgan was the country's strongest bank through the financial crisis. Last year it raised capital for businesses when others couldn't; it was the top merger and acquisitions advisor; and it never posted a quarterly loss. --Scott Cendrowski

Rank: 10 (Previous rank: 9)
CEO: Mark V. Hurd
As the biggest technology company by sales, HP now competes with every other IT shop that offers one-stop shopping for corporate buyers and consumers alike. IBM remains HP's biggest foe on the services front, while Oracle's purchase of server-maker Sun challenged HP on corporate hardware.
The company's pending acquisition of networking-gear manufacturer 3Com puts this Silicon Valley pioneer in the crosshairs of Cisco. Printers once accounted for the biggest chunk of HP's profits, but with size comes diversity: Services, software and computers are all making healthy bottom-line contributions now too. --Adam Lashinsky

Rank: 11 (Previous rank: 13)
CEO: Warren E. Buffett
If Warren Buffett has lost a step, it didn't show in 2009. Berkshire rolled up its gaudiest net-worth gain ever and arranged its biggest deal, a $26 billion purchase of railroad Burlington Northern that was completed in 2010. The company also announced a stock split that brings Berkshire ownership within reach for those reluctant to plunk down thousands of dollars for a single share.
Skeptics complain Buffett has drifted from his value-seeking discipline, but the stock is up 23% this year. Maybe that's why fans spend so much time debating who might eventually fill his rather large shoes. --Colin Barr

Rank: 12 (Previous rank: 12)
CEO: Vikram S. Pandit
The sickest of the major banks is finally getting healthier. In 2009, Citigroup split itself in two -- a good bank and a bad bank -- in its effort to sell off more than $500 billion in toxic assets. After passing a government stress test, Citi officially paid back TARP funds to the U.S. Government in 2009.
Still, a $25 billion bounce from last year's losses couldn't move Citi into the black. It lost $1.6 billion during the year because of consumer credit losses and costs to repay TARP. --S.C.

Rank: 13 (Previous rank: 17)
CEO: Ivan G. Seidenberg
Like chief rival, AT&T, Verizon also missed this year's stock market rally. In the year period ending April 1, Verizon's stock was down almost 4% while the S&P 500 rose 41%. In the same period, Verizon partner Motorola came back from the dead with Droid and was up 52%.
Not even the chorus of rumors saying Verizon will get an iPhone has helped. For all the nifty devices Verizon is stocking, what it can't buy is growth. Analysts project an average annual earnings growth rate of just 5% over the next few years. That's nothing to phone home about. --M.C.

Rank: 14 (Previous rank: 15)
CEO: John H. Hammergren
In March, McKesson finally washed its hands of a decade-old accounting scandal when former CEO Charles McCall was sentenced to 10 years in prison. Maybe that will help people refocus on the company's impressive fundamentals.
With revenues of more than $100 billion, McKesson generates far more top line than its cooler corporate neighbors in Silicon Valley. The company's strong performance during the recession recently prompted Standard & Poor's to upgrade the company's rating.
Best known as the nation's largest distributor of pharmaceuticals -- the company processes some 4.5 million items a day -- McKesson is making inroads on others fronts, digitizing patient records and developing after-hours prescription machines. --P.N.

Rank: 15 (Previous rank: 6)
CEO: Edward E. Whitacre Jr.
2009 was a tornado for the 101-year-old automaker. There were three CEOs, four divested car brands, and a bankruptcy reorganization that left American taxpayers as its largest shareholders. Don't forget 2,300 eliminated dealers, 10 closed plants, and 21,000 layoffs.
The world's second-largest automaker is now run by CEO Ed Whitacre and CFO Christopher P. Liddell, neither of whom have previous auto experience. Liddell says GM has a “reasonable chance” of making a profit in 2010, expects to pay back the remaining $5.6 billion in government loans by June, and plans a public stock offering “as soon as it makes sense.” --Alex Taylor III

Rank: 16 (Previous rank: 245)
CEO: Robert Benmosche
The good news: AIG chief Robert Benmosche is making good on his promise to repay $180 billion in government bailout money. The company sold two insurance operations earlier this year for $50 billion, most of which will go to repaying its debt to the government.
The bad news: AIG lost $11 billion last year. Then there's the company's ugly balance sheet -- $140 billion in debt, $150 billion worth of credit default swaps -- its numerous legal entanglements, government investigations, and inability to hold onto key executives. It all makes AIG stock, which has gyrated wildly in the past year, better to ogle that own. --P.N.