It does have multiplayer. Honestly, I rarely play it. Campaign is where it's at.
ALSO just realized that it's only for the original Mount & Blade that I've never actually played. Warband is $5, and Fire & Sword at $2.50.
And actually, I just saw that you can pre-order their new Warband DLC, Viking Conquest, for $12. It says it's coming out next month.
EDIT: Oh yeah, these are sale prices for the weekend