Right now on battle.net, you can upgrade your copy of Overwatch to the Origins Edition for $10, which is 50% off of the normal price of upgrading.
It's worth noting that there is a $10 flat discount on the full Origins Edition, but that's not as appealing considering the upcoming $40 GCU deal listed in this other thread
But this is a great deal for existing players who want access to the following:
- Overwatch: 5 in-game origin skins: Overgrown Bastion, Security Chief Pharah, Strike-Commander Morrison, Blackwatch Reyes, and Slipstream Tracer.
- Heroes of the Storm: Tracer hero
- World of Warcraft: Baby Winston pet
- Hearthstone: Overwatch card back
- Diablo III: Mercy's wings
- Starcraft II: Player portraits for Tracer, Reaper, Pharah, Winston, Bastion, and Soldier: 76