Did you know that you now have an opportunity to convert your traditional 401(k) account to a Roth account. This means that you can pay taxes now (at current rates), and assuming that the Internal Revenue Code does not change, pay no future taxes on both those amounts and their future in-plan investment earnings. In a potentially rising tax rate environment, this will be a good idea for some (each person's situation is different and before making such a decision, you should consult your personal financial and tax advisors). As is frequently the case, the rules are not as simple as we might like.
Learn more here: http://www.aon.com/attachments/roth_conversions_oct2010.pdf