No single game sold me on the PS4, just as no single game sold me on the PS3 nor the X360. What sells me consoles is the hardware itself, the controllers, the operating system that comes with said console, and knowing that it _will_ have the multiplats I expect and the exclusives I expect.
I have loved my PS3 since I got it because it works like I expect it to. The games I play on it work as I expect them to, with the best controller design. I expect the PS4 will be the same.
This new gen has already disappointed me significantly, except for the PS4, which has disappointed me the least so far. The Wii U is just so badly designed imo that for the first time ever I have seriously considered not buying a Nintendo home console. The XONE still maintains the things I disliked about my X360; controller, UI, gamer score, and adds more on top, kinect, and a schitzo DRM policy that I dunno wtf they are going to attempt to jam down my throat in the future. I probably wont buy the XONE for at least 2 years.
That leaves only the PS4, which despite its now largely delayed exclusives, still manages to be cheaper, better designed, better controller and UI, and have all the non-exclusive games that will last long enough until the exclusives start to trickle in.