I think that when it comes down to it people judge next-gen by the graphics of the games, even those who say that graphics are not the most important part of a game. Look at inFAMOUS: Second Son (which by all rights should look worse with it being an open-world game) and then look at Titanfall, one is extremely pretty and the other is less so, meaning one is decidedly next-gen and the other is not.
The Xbox One is an extremely undesirable console in the eyes of most gamers, and that has filtered down to the casual masses. PlayStation 4 hype is still through the roof, the console is sold-out almost everywhere, it is cheaper, and it is more powerful. People know these facts, and that is why the PlayStation bundle is selling more than the Titanfall bundle.
