Imagine classic western movies. Put control in the shooting and you have RDR.
But my biggest dissapointment was the story, seriously, go and buy ANY movie from old west, the story it's the same, for short, after i ended the game i haven't felt that it was worth playing.
Prototype was hard, but worth playing, good story with a decent gameplay all along.
Assassin's Creed Brotherhood was a game with loads of flaws and some things that doesn't looked like assassins, but in the end it was worth getting all the way through to the end.
Red Dead Redemption was NOT worth getting to the end, perhaps the multiplayer may be fun, but i wasn't amused at all with the Single Player experience.
In the end, DO NOT BELIEVE THE HYPE.
This game doesn't deserve to be the Game of the Year neither the Best Story, and those were the only reasons i played.
This is only my opinion, but i would advise you to rent first.