Some interesting points in the thread. I could be mistaken but it seems like the core four 'agreements' or as close as you'll get in a thread are:
1) games due to their nature 'age' faster than books/movies and therefore don't hold their price or repeat value to the same extent (i.e you pay full price today for a book written twenty years ago or even hundreds of years ago, this is not the way with games). This applies to good games vs bad and particularly games without online MP. Also genuinely poor/unliked games will be ditched pretty fast and that's what you get for making a poor game.
2) used games are therefore even more prevalent than with books/movies and are just a fact of life that developers need to accept. Good games will help but they'll still age fast. MP helps - but pls don't make everything MP as that won't work either! Good SP games still have a lot of value to those that like them, just make 'em good.
3) used games / new games need to be clearly separated and perhaps even a limit of when games can be taken back and termed 'used'. Also 'pre-owned' must be clearly marked as such.
4) DLC and content you unlock over time would help. I think Burnout is a great example of this BTW - I know so many people who hung onto the game as they wanted the free DLC coming and felt the game was still 'alive' in a sense. It also got others to buy the game much later than normal by slowly building the attractiveness of the game.
Seems like a fair bunch of points the majority have made.
The interesting one for me is the good/bad game dynamic. No-one wants to hang onto a game that is bad, nor give more money to the developers - and nor should they.
A good game however, particularly SP, shouldn't be punished by being played, then offloaded quickly because the SP is complete and hurt ongoing full price sales. This is the one that worries me. I do see pre-owned hurting SP games (which I prefer to MP) and the industry response is obvious (make the focus MP over SP) and developers turning away from big, expensive SP experiences.
Try to be reasonable... its easier than you think...
