"The economy is definitely improving." So said General Electric (NYSE:GE) CEO Jeffrey Immelt this morning, before detailing fourth-quarter and full-year results for the world's largest company.

Earnings came in at $0.45 per share during the quarter, on total revenue of $40 billion. For the year, EPS jumped 6% to $1.49 and revenue inched up 1% to $134 billion. Eight out of its 13 business segments saw full-year double-digit earnings growth: Commercial Finance, Consumer Finance, Consumer Products, Insurance, Medical Systems, NBC, Specialty Materials, and Transportation Systems.

Moving to the cash flow statement, cash from operations rose 28% to $12.9 billion. Management projects about 10% growth in this area for 2004.

Because GE's businesses range from light bulbs to jet engines to commercial financing to broadcasting, the company is often used as a barometer for the general state of the economy. And Immelt seems genuinely upbeat about 2004 and beyond. "The company is in great shape, the market looks good, we delivered what we said we were going to deliver, and we've got good momentum," he said during this morning's conference call (transcript provided by CCBN StreetEvents).

And, with fourth-quarter orders up by 19%, "It really is the broadest orders strength we've seen probably since 2000."

It's a strange time for the market and the economy. On the one hand, bellwethers such as GE, IBM (NYSE:IBM), and Intel (NASDAQ:INTC) are delivering strong results and projecting optimism. At the same time, distinguished voices such as Bill Mann and Whitney Tilson are urging caution.

Only time will tell if the economy will continue to move forward in 2004 as GE and the others seem to think it will. In the meantime, our normal advice applies here: Only have money in the market if you plan to keep it there for a long time -- at least five years, preferably longer. That way, you're better able to ride out the inevitable ups and downs, and it's far less likely you'll be forced to withdraw funds at a loss.