Mojang developer Jens Bergensten has revealed that update 1.5 for Minecraft will be going live early next month.
Minecraft 1.5 will be released in roughly 2 weeks, early March
— Jens Bergensten (@jeb_) February 24, 2013
Version 1.5 is known as the Redstone Update, and will make changes to redstone ore, giving it variable signal strength and adding a new capacitor block.
Image: Minecraft Forum