Blizzard has announced that their item bundles for MOBA Heroes of the Storm are to become "dynamic" with their price discounted by the cost of any items that you've already purchased.
It's not quite the selfless move it sounds--items you've purchased only have their bundle price (not their individual sale price) discounted in cases where that differs--item bundles with just two items within remain static, and you can't try and get Stimpacks or bonus gold from bundles where one or the other are the only items from the bundle you don't already own (if it ever would make sense to do that.)
They're also using this moment to switch up some of the bundles, with the Nexus Bundle being replaced by the Storm Bundle. What this means is the "Nazeebra Mount" (exclusive to the Nexus Bundle) is being removed from the shop, so if you want to pick up this mount specifically, you'll have to grab it within one week of patch day.
However, if you're a player who has already purchased duplicate items from the shop (possibly to grab that mount) you'll be getting some of that gold back. Blizzard says to watch out for an e-mail from them in the next few days.