Hahaha you know... I was wondering the same thing. I think this will replace cIOS Downgrader just like Savegame Manager will replace Savegame Extractor-Savegame Installer. But that is just me guessing.
What it does is downgrade or upgrade to any Wii firmware while still maintaining the trucha bug. Cios downgrader could only go up to 3.4 and didn't maintain the trucha bug. Basically it lets you go to any Wii firmware while still maintaining everything homebrew related (like WAD installations).