I almost always purchase used games or games that are new but have been out for years. I am a Playstation person myself and the VP of Sony said that they would do the right thing, though didn't confirm or deny that they would do it.
My bet is that used games may have some limitations, like only one usage for the first three months the game is released and will make exceptions for places like gamefly that rent games, but won't restrict the use of used games for ever.
I'm with you (Playstation guy also), as I only buy used games or games that have been out a while too, then sell them right after I beat them. Doing it this way, I figured out I basically play games for free or at minimal cost. Example, I bought Assassins Creed 2 and Batman Arkham Asylum used last fall for about $10 each. Then sold AC2 for $12 and Batman for $9 after I beat them. I basically got paid $2 to play Assassins Creed and only had to pay $1 to play Batman. Good deal for me.
I see no reason why manufacturers should care about consumers that they don't make money off of. People who only buy used games are not doing anything unethical, but none of the money goes to hardware producers and none of the money goes to game developers. Services like Gamefly are great for gamers, but probably horrible for game producers. Do devs see a cent from GameStop's trade ins?
On the other hand, I would want games to be cheaper if there is no ability to sell back or trade. As it is, console games don't get the great sales that PC games get on Steam.
Perhaps they could consider a one month game rental system for half price.