President Obama won another year of tax reductions for workers in a major tax compromise that he signed into law right before Christmas. But thanks to the intricacies of tax law, some workers will get slightly bigger breaks in 2011, while others do slightly worse.

To review the history: President Obama campaigned on tax breaks for workers, proposing a rebate that would equal about $500 a year -- technically, the first 6.2 percent of the first $8,100 of earnings. Congress accepted his proposal, including it in the economic stimulus of 2009, but they trimmed it back slightly to a maximum of $400. The tax credit, known as "Making Work Pay," expired at the end of 2011.

So the first time around Obama got slightly less than he wanted, and he only got it for two years. At the time, we rated his promise Compromise.

In December 2010, Obama brokered a broad tax deal with Republicans, avoiding automatic tax increases that were scheduled to take effect and extending some of the tax breaks from the stimulus. But the Making Work Pay tax credit didn't make the package. Instead, the bipartisan compromise created a 2 percent tax "holiday" from payroll taxes that workers pay toward Social Security.

The Social Security tax cut needs a little explaining unless you're intimately familiar with payroll taxes. Normally, workers pay 6.2 percent in payroll taxes on up to $106,800 of their earnings. (Employers pay another 6.2 percent, while the self-employed are generally on the hook for the full 12.4 percent.) The tax cut means workers will pay only 4.2 percent of their earnings. So if you make $106,800 or more, you could save $2,136 in payroll taxes in 2011 -- clearly much more than the Making Work Pay tax credit.

But let's say you make much less than that. We did a back-of-the-envelope calculation and found that if you make less than $20,000, you will likely be worse off under the new plan, getting a smaller tax break than the $400 that was part of the stimulus.

The nonpartisan Tax Policy Center ran a preliminary analysis comparing the tax breaks and found that, generally speaking, people who earn less than $10,000 would probably see higher taxes of about $203 a year. Those who earn between $10,000 and $20,000 could see a an increase of about $185 per year. We should note that's still a little better than before Obama took office; it's just not as good as 2010.

Still, the Tax Policy Center analysis shows that about two-thirds of tax payers would be the same or better off under the the Social Security tax cut than under Making Work Pay. The more money you make, the better off you are.

Finally, we should point out that most workers will see these tax changes in the form of small increases (or decreases, in the case of lower earners) in their regular paychecks. The Obama administration has said that it favors giving out tax breaks through people's paychecks because recipients are more likely to spend the extra dollars in their paychecks and thus stimulate the economy.

So what does all this mean for our rating of Obama's tax promise?

Well, the Social Security tax cut is similar to Making Work Pay, but it's not the same. Many tax payers will likely be better off the new plan, but not all will be. And, the Social Security tax cut is only for one year. Under current law, in 2012 workers will have neither the Social Security tax cut nor the Making Work Pay, so their tax rates will be the same as when Obama took office. We anticipate checking back on on this promise then.

Taking all this together, we rate this promise Compromise.