Game of the year? Really?
The side missions were kinda fun but if you start one, then ride the horse for 10 minutes to get to your destination and then end up dying, you start right back at the beginning and have to take the long horse ride again which I felt was unnecessary as with the main story missions you can retry from the last checkpoint.
It is however a very pretty looking game but like others have said, take GTA IV, replace the roads with sand, the cars with horses and you have Red Dead Redemption.
I won't say it's a bad game but I feel its definitely over rated.