LaVorgna, who had forecast 4 percent growth for the quarter, said he will not change his forecast for the subsequent revisions. Third quarter GDP was ultimately revised to 4.1 percent growth from the government's initial estimate of 2.8 percent. He expects more than 3 percent for the first quarter, while a number of economists are more in the 2.5 percent range.
"We're lucky we got a solid 3 percent number. It kind of clears the air," said Rupkey. "If the jobs data is strong, that's OK, but if the jobs data is more mixed but GDP comes back, then we and the Fed can lean on that and say progress in the economy has been made. It's a good outcome today. A good result."
Some economists were skeptical of other details within the number. The export figure, for instance, helped add 1.3 percent to GDP. Exports rose 11.4 percent and imports were up 0.9 percent.
(Read more: Households, trade boost GDP)
"Such a combination is unlikely to prove a sustainable source of growth in 2014," wrote Barclays economists. "Inventories added 0.4 [percentage points]. Alongside the 1.7pp addition in Q3 (and sizeable contributions in Q1 and Q2 as well) this adds up to a very significant inventory build during 2013 (at least based on the current data vintage, the picture may look rather different following future revisions)."
Inventories were cited as a potential headwind by several economists. "Inventories jumped in the third quarter and then followed by even more accumulation in the fourth. Farm stocks have been a big part of the rise," wrote Citigroup economists. "While we think the gains in inventories represent a catch-up to rising demand, the $128 billion total change seems unsustainable."
Citigroup economists also point to the trade growth as unsustainable and inventories at levels that will not be maintained. "Today's report, while an indication of continued improvement in economic activity, suggests that growth at the start of the year may slip to the 1½ percent to 2 percent range," they noted. They added they expect growth to continue to strengthen toward the 3 percent range for all of 2014.
An important number that has been showing improvement is the real final sales of domestic product, which rose to 2.8 percent in the fourth quarter, compared with an increase of 2.5 percent in the prior quarter.
—By CNBC's Patti Domm. Follow her on Twitter