A lack of a story gives the game a long playing life.
Mount and Blade has a horse combat system that exceeds those of all others games in terms of realism- even Assassins Creed.
Combat is the rewarding bit as quests may tend to get repetitive. Think of battle as an excerpt from the pages of an RTS where you are in direct control of only the general. All other units move and attack the verbal orders that you bark out. Given that battle maps are randomly generated and that there is a treasure trove of armour, weapons and steeds in the game the thrill of riding into battle never seems to go down.
The game was developed by a husband and wife team from Turkey. I guess its only appropriate for gamers to doff their berets to them to come up which such a great game. True, it maybe a bit unattractive graphically but such attention to detail will probably take a backseat once combat is explored.