Just based on the above pics, I would have to learn towards 2 1/2. Keep in mind it is late in the year and a 2 1/2 SHOULD have a little more wear now than they did in October or November.
But by no means am I saying this deer wasn't 3 1/2. If I had that jawbone in my hand, I might be saying 3 1/2. Or if I had actually seen that buck on the hoof, I might be saying 3 1/2.
Each deer is an individual, and some have faster or slower-wearing teeth, just like humans. My bet is this buck may have been 3 1/2, but just based on the above pics, I'd have to "guess" 2 1/2.
By the way, Will, it is statisically unlikely this buck was 2 1/2 if he had 10" G-2's, and I believe he must have "looked" like a 3 1/2 or older for you to have shot him. But it is possible he was only 2 1/2.