Like so many things "It Depends". If you intend to keep the car for a long time, say 10 years, then it won't matter much which year you buy for depreciation. However, you have to do the math with the interest rates. If you have excellent credit, you'll get pretty low rates anyway - under 4%. Factor in any incentives on the leftover too, and how much you will be financing. If the purchase price is similar for both years, I'd be inclined to buy the 2013 and make a large down payment, minimizing the amount financed, and the total amount of interest paid. Check with your bank or credit union first to see what they'll offer you for rates and then let the dealer try to beat it (often, they can). I agree with the 36 month term.
One reason to go with the newer car if prices are similar and there are no real changes and you intend to keep for a long time is the potential for insurance payment in the event of a totalled wreck. If someone smashes your 2012, it will be valued by the insurance company as a 1 year old car, while the 2013 will be valued as new and you would get a bigger settlement check. Let's hope it doesn't happen to you, but it did happen to my new subaru and I was happy that I hadn't chosen a brand with high depreciation or a leftover. I'd still consider a leftover - but it would have to be deeply discounted.