I know Social Security beneficiaries will not receive a cost-of-living increase in 2010 because the inflation rate has been so low. (see A Bailout for Seniors). How does the lack of inflation affect retirement-savings plans? Could contribution limits for 2010 decrease?

More than three dozen tax benefits are adjusted for inflation every year based on the change in the third-quarter consumer price index from one year to the next. Because there was no increase in the CPI from 2008 to 2009, many of these benefits will remain the same or will change only slightly in 2010.

But contribution limits will not be reduced. The IRS recently announced that the maximum will remain $16,500 for 401(k)s, the federal government's Thrift Savings Plan and other retirement-savings plans. People 50 or older can continue to make catch-up contributions of up to $5,500.

You'll still be able to contribute up to $5,000 to a Roth IRA in 2010 (and make a catch-up contribution of $1,000 if you're 50 or older). And the maximum income limits for Roth IRA contributions will change only slightly, rising from $166,000 to $167,000 in 2010 for married couples filing jointly, and remaining unchanged at $105,000 for singles.

Another key IRA change for 2010, which has nothing to do with the CPI figures, is the elimination of the $100,000 income limit for rolling over a traditional IRA to a Roth. So even if you earn too much to contribute to a Roth IRA in 2010, you can still contribute to a traditional IRA and immediately roll the traditional IRA over to a Roth. See The New Roth Rollover Rules Explained for more details and information about how the conversion is taxed, which can be tricky if you have other traditional IRA accounts.

The IRS announced several other tax-related limits for 2010. Income-tax brackets will change slightly. For example, the income threshold separating the 15% and 25% tax brackets will rise by $100, from $67,900 to $68,000. The annual gift-tax exclusion will remain unchanged at $13,000 -- which means that taxpayers may give up to $13,000 per person in 2010 without being subject to the gift tax. And the standard deduction remains unchanged at $11,400 for married couples filing jointly and $5,700 for singles.