According to the ESRB, this game contains: Blood, Violence
Parents can expect loads of gunplay, movie-like violence, and gushes of blood coming from well-placed headshots. It's not excessive, but the shooting is the game's central mechanic. There are no sexual situations, and an extremely minute amount of questionable language.
Fans of Western themes will have a heyday. This is by far the best Western game I've ever seen, and plays like a string of movie highlights complete with horses, trains, and high noon shootouts. If you like cowboys, this is a must-buy.
Action gamers will get a great singleplayer adventure complete with a very robust multiplayer side. The replay value is fairly high, with challenges available after completion and a ton of unlockables. It's rough, but a lot of fun.
Deaf and Hard of Hearing gamers will have no problems. There is full text for all spoken dialogue, and most bullets have a tracer-like trail making it easy to see where snipers are hiding without relying on sound. Great job, Rockstar.