>>719097802 (OP)
I would argue that there is a delineation point between the early 7th gen 2005-2007 mid 7th gen 2008-aprox 2011 and the late 7th gen 2012-2014.
The main factors defining them are the prevalence of FPS the the primary genre, the shrinkage of the AA marketplace, the prevalence of the indie market, the separation of the PC and console markets and the optimization of online features.
Because pre-COD4 the 7th gen was very much an extension of the 6th and during the mid years Xbox in particular was defined by its indie and arcade marketplaces as much as its big titles. And on top of that this was still the era where most PC ports of console focused games sucked and so the cultural separation between PC and Console was still upheld.
This all got blown away by the sheer force of greed by the end of the generations life however, and we have lived in an era that is mostly the same since. But I don't think one should discount the unique and now gone culture of the gen before it become ultra homogenized and its popular IP were milked forever.