I'm a huge fan of games that pay attention to the small details. More often than not a game will get some bonus points, and even make me overlook other flaws, if they get the little things right. A prime example would be the Amazing Spider-man game, who took the time to animate web-cartridge reloads on Spider-man. It was a small touch that made the nerd in me crazy excited!
There's been tons of similar examples in other games, and Peter Molyneux has made a career for himself promising details for all his titles (though they are rarely delivered upon). Each and every time I get instantly excited about the game.
In an interview with Projekt Red, GameStar unearthed some pretty cool features that The Witcher 3: Wild Hunt will offer in the vain of insane attention to detail. The internet has been blowing up today over one feature in particular: Beard growth.
As the game progresses it seems Geralt (the main character) will grow his beard out as well. According to the interview you'll go from clean shaven to the proud owner of a lengthy beard (though it is noted it will not be "Gandalf-length").
Other important changes to the game which are provided via the translation of the interview's key points, by NeoGaf's His Majesty, include an increase in the amount of gore, a 900p resolution on the Xbox One, bartering and theft.