This gen isn't going to last anywhere near 8 years. The systems are far too weak for that.
I predict the next Nintendo in late 2016, the next Xbox in late 2017/early 2018 and the next PlayStation in late 2018.
Hardware owned:
PC, PS4, 3DS, Wii, Xbox 360, PS3
Most anticipated games (near to mid future):
Zelda U/NX
The Last Guardian