That is a question you may be contemplating soon due to a change in the tax law. Starting in 2010, anyone with a Traditional IRA will be able to convert it to a Roth IRA, regardless of income or filing status.
One difference between a Traditional IRA and a Roth IRA is the timing of the taxation of the account assets. With a Traditional IRA, your contributions may qualify for a tax deduction, but your withdrawals will be taxed as ordinary income. In contrast, while your contributions to a Roth IRA aren’t tax-deductible, account earnings aren’t taxed and earnings can be withdrawn tax-free once you are at least age 59½ and five years have passed since your first Roth contribution. (Roth contributions are always distributed tax-free.)
Some people can benefit over the long term by "converting" (transferring) their Traditional IRA assets to a Roth IRA. The conversion is a taxable event, but all future Roth IRA earnings will be tax-free if all requirements are met.
To convert a Traditional IRA to a Roth IRA, a taxpayer’s modified adjusted gross income for the year generally can’t exceed $100,000.
The income limitations on who can convert a Traditional IRA to a Roth IRA will no longer apply, starting in 2010. No matter how high your income, you’ll be able to take advantage of a Roth IRA’s tax benefits. And, if you convert in 2010, you can spread the tax bill out over the next two years (2011 and 2012).
High-income earners can take steps now to make the most of the new rule. Since there are no income restrictions on nondeductible contributions to a Traditional IRA, consider contributing now to a Traditional IRA. You can contribute up to $5,000 in 2009 (even more if you are age 50 or older). Then convert to a Roth IRA after 2009 and remember, after conversion, all earnings on the Roth IRA balance will be tax-free if you meet the distribution requirements.