I don't care that much for B/C because I will most likely keep 1 of my 3 Xboxs to play my 100+ discs laying around.
But i'm sure a lot of gamers would like to sell their 360 for the new Xbox because they don't want multiple consoles hooked up.
Also, just because a new system comes out doesn't automatically mean that the past generation of games become useless & no one wants to play them.
Say the next Xbox comes out & it doesn't play Gears of War 3, now when I get other friends online who haven't spent the $$$ on the next Xbox & they want me to play Gears 3, i'll need a way to play it with them. I'm not going to shun my friends for not spending money on a new console.
It is clear that our Profile will carry over, because it did with the OX to 360. I just hope they don't give us a problem transferring over all of our Arcade titles & other various digital purchases. That will bother me.
As for Achievements, although they don't really do anything for us gamers in the real world, they are still far from pointless & is a great addition to this gaming generation.
Having a whole log of everything I played throughout my years on the 360 is awesome. I wish I could go to a website & see all the games I played on the Dreamcast, N64, Genesis, NES, PS2, etc.
Comparing with friends is also a great feature to either get help or give help to fellow gamers.
MS would be complete fools to let this mentality go.
XBOX ONE has the world's best Exclusive, which is me! I'll be playing it online.