The U.S. economy exceeded expectations by growing at a 3.9 percent annual rate, which the Los Angeles Times deems "solid."

"The figure was unexpectedly better than the 3.5 percent annual rate the government reported in its first estimate last month," the newspaper explains, quoting figures released by the U.S. Department of Commerce's Bureau of Economic Analysis. "Economists had forecast the growth rate would be revised down to 3.3 percent."

The Commerce Department hands out three estimates of total economic output, or gross domestic product, for each quarter.

Joseph Lake, an analyst for the Economist Intelligence Unit, told Forbes that the U.S. economy was "in rude health, outperforming most countries in the developed world." He said the economy's annual growth rate has bee over 3 percent for four out of the last five quarters.

"[The U.S.] is finally casting aside the shackles imposed by the financial crisis,'" he explained.

Lake added that the biggest gainers were net exports and government spending, but added that "their momentum is unlikely to persist."

Consumer spending, business investment in equipment and inventory buildup all performed stronger than initially estimated, MarketWatch points out, which led to the "upward revision" in growth for the period.

"Third-quarter growth still was down from the 4.6 percent pace in the second quarter," the Los Angeles Times cautioned. "But the decline was expected as much of the spring activity came from pent-up demand after the economy sharply contracted during a winter marked by severe weather."

Jim Baird, chief investment officer at Plante Moran Financial Advisors, suggested that the good performance during spring and summer may signal a true recovery five years after the end of the Great Recession.

"The third-quarter performance dovetails with a raft of evidence showing that the trajectory of an economy has accelerated sharply after a big letdown early in the year," MarketWatch reports. "The [U.S.] is on track to add the most new jobs since 1999 and sectors from manufacturing to retail continue to gain strength."