Actually yes... The people who by PlayStation consoles and the people who buy Xbox consoles are actually slightly different in terms of taste because of exclusive games from consoles past. For example, because Final Fantasy VII was such a massive hit that it put JRPGs on the map, PlayStation fans generally buy consoles for JRPGs and that ends up showing when comparing sales between the PS3 version and the 360 version of a game in that genre. In addition, PlayStation platforms are pretty much assured the genre. Conversely, because Halo 1 was such a massive hit on the original Xbox put FPS games on the map, Xbox fans generally buy consoles for FPS games. Xbox platforms are assured at least Halo as an exclusive, even if everything else sells on both systems. To put it in perspective, this is also why Nintendo does better with family-friendly games and platformers... Basically, each platform has cultivated certain genres because of their first-party games or exclusive third-party games which mark the lines for fans of those genres even in an era where every third-party is multiplatform.
Nintendo: Platformers, Party Games, Local Multiplayer
Sony: JRPGs, Fighters, Single Player
Microsoft: FPS, WRPGs, Online Multiplayer
One can see that whenever a certain console is successful, its particular style becomes more prevalent while competitors' styles fade into the background, but the styles each company has were pretty much defined by the PS2/GC/Xbox era and have not changed all that much since then.