Your accountant will be able to clarify this, but because some of your expenses were incurred in 2010, you can actually apply for your tax credit now (that is,if things haven't changed since we did this -- we were advised that we should go ahead and apply and not wait until the following year).
Our situation was similar to yours - we went to orientation in 2008, took placement of Hugo in 2009, and finalized in 2010. But all of our expenses from 2008 (agency fees, orientation, travel expenses, escrow expenses, etc) added up to just shy of the credit amount, so we filed for the credit on our 2009 taxes (in 2010 - BEFORE we finalized) and got it, no problem. Then we filed for the remaining amount of the credit on our 2010 taxes, after we finalized.
Just seemed like if we could get a chunk of the credit a year earlier, why wait? Anyway, hope this makes sense and hope your accountant is helpful!
This is what we're planning to do, too. We applied for an adoption tax id number for Joseph as soon as we got back home from Texas and received it sometime in December, so we should be good to go.