1. How would I verify this is the case before the end of the year?

Do a projection of your tax return. You'll only need to work on page 1 of the 1040, as you just need to get to AGI. You can get draft 2012 tax forms and instructions here: http://apps.irs.gov/app/picklist/list/draftTaxForms.html

2. If that's the case, what's the best way for me to withdraw that non-deductable contribution from the traditional IRA and place it in the Roth IRA for TY 2012?

You would need to recharacterize the current year contribution from a traditional IRA to a Roth IRA. I believe you have until April 15 2013 to recharacterize 2012 contributions.

If you are going to be close to this threshold every year, it might make sense to delay making your IRA contributions until you've prepared your tax returns. You have until the initial filing deadline (April 15) to make IRA contributions for the prior year.

--Peter