I'm still iffy on this whole concept. On the one hand, I fully respect developer's desire to make as much profit on the game as they can and offering "enticements" for new copies is a good way to do it.
On the other hand, I don't like the notion that devs will start removing "integral", for lack of a better word, aspects of the game in order to punish those who buy the game used.
I work at Gamestop and there are very few customers who come in looking for major releases in the used section immediately after the game comes out.
However, one thing I tend to notice is that many people buy used because "it's cheaper." Maybe if developers would lower the prices of their games a bit quicker, buying new would feel like a better idea.
Oh well, we'll see how it goes.
