I doubt any 360 games will be playable on nextbox. Your best bet might be PS3 -> PS4 since Sony has a pretty good history of backwards compatibility (PS2 fuckup notwithstanding).
I guess as long as my 360 doesn't die, I am okay but whatever, I just play the new stuff. Since hackers already dump XBLA games anyway, so you can always play these illegitimately.
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