I need to repave my machine. I've made progress in the StarCraft 2 Wings of Liberty Campaign that I don't want to lose. I believe the achievements I've unlocked are tied to my battle.net account and will therefore be kept.
What I am unsure of is if my specific campaign progress will need to be backed up before I wipe the hard drive. I don't want to have to replay missions I've already completed or re-buy Armory upgrades.
Do I need to backup any sort of save game information or is it all online with battle.net?