I started playing this the other day, but I held off posting about it just in case it was too good to be true. Was I wrong.
I've played it through twice now (inc. all side missions) and it is still as exciting and fast paced as ever (3rd time now). It feels very arcady, but this is pulled off fantastically as you rack up kills in quick-fire mode with a wonderful ker-ching noise. The experience ranges from fast frantic gunfights, throwing your horse viciously at the enemy, to trotting along herding some cattle looking at a nice sunset. Very therapeutic
Get this game. Get it. Get it for christmas. If Santa hates you, get it anyway.