This game is just so amazing, awesome graphics, beautiful surroundings.
Tumbleweed rolling along, wind blowing sand in the air while your clothes move in the wind, rain pouring down on the countryside causing poodles everywhere. And thunderstorms.. oh my, so awesome!
Wildlife that changes depending on the time of day/night, vultures that sit on the wooden entrance of a ghost town, telling you get out of here or your dead.
Seeing clouds move at night uncovering the moon giving you some more light in the darkness while you are looking for a spot to set up camp, hearing gun shots in the distance and hearing the howling of wolves and coyotes coming closer and closer to you while your horse starts to get nervous, until it starts to move around anxiously and runs off..
Also the town life is so amazingly detailed. Take for example the Saloon at Armadillo. At 6 AM in the morning you will find no one in there, not even a barman or a cleaner. Around noon or so you will start seeing the personal go in the saloon starting to get things ready. Around 4PM people start quitting there job and start getting in to the saloon (still not busy however). People start to drink but are sober. Later in the evening the Saloon starts to get busy, weird folk start to get in and people get drunk (you can hear it in the way they talk and how they move, some can hardly walk). Later at night (2PM or so) people start to leave, after the customers have left. The personal will start cleaning and when finished leave until it's completely empty again.