Bhagavatula, like Rupkey, did not raise his 2011 GDP forecast because of the stimulus package.
Like other economists, they expected the tax cuts to be extended in some form.
"I think most people thought they would be extended," adds Robert Brusca, chief economist at FAO Economics. "If the question is how much things change because of this legislation, the answer is not much."
If anticipation is a key consideration to the psychological equation, so may be perception. The legislative package doesn't actually cut income taxes. It does not raise them, so in that way it does not put more money in people's pocket.
"The way it is being talked about is kind of peculiar," say Brusca. "If anything has an impact, it is will most likely be the cut in payroll taxes, which was not expected. It will immediately increase take-home pay for 155 million workers. For an annual income of $50,000, for instance, it means $1,000 less in taxes."
On a broader basis, that represents about $120 billion, less than 1 percent of the nation's GDP, which was $14.75 trillion in the third quarter, based on the final report issued Wednesday.
Economists say that could mean anywhere between $20 billion and $70 billion in spending. The Joint Economic Committee on Taxation puts the impact at $60 billion.
At the same time, GDP estimates for 2011 vary widely, ranging from the around 2.5 percent to 4.5 percent, with the consensus in the 3.5 percent range. Oddly, some see growth at its strongest in the fourth quarter, while others see it slumping.
Consumers and taxpayers, however, may have more than the usual factors driving behavior.
The tax package came amid growing concerns about the ballooning budget deficit and a tsunami of budget cut and tax-hike proposlas from the president's deficit reduction commission.
"What's more debatable is how the average consumer is thinking about tax rates in the long run," says Pandl. "There's a pretty broad recognition that the state of govenment finances is poor. Real spending cuts and tax increases are inevitable."
Nomura is among those that see GDP growth slowing dramaqtically during the the year, from 3.8 percent in the first quarter to 2.5 percent in the fourth. Brusca is also forecasting a late slowdown, but not as severe.
Any consumer boom then may be a short-lived event in the beginning of the year; some even suggest it has already started, making a small contribution to the better-than-expected holiday spending.
Maybe, says Brusca. "You recognize you're going to have higher disposabler income, so it has a temporary kick."
"You create s a feel good effect for the economy," adds Rupkey.
Another wild card is gasoline prices, which have been creeping up during the second half of the year and are now above $3 dollars a gallon. Along with stock prices and the jobless rate, they are one of the keys to consumer sentiment.
Rising gasoline prices in 2008 put a damper on consumer spending, with some saying they absorbed a good part of the tax renate money.
"If they move up dramatically it will have an impact on spending," says Pandl.