What is WACK in Windows store development?

In the Windows 8 Store documentation, one of the things to take note is that ‘JS and Boo scripts won’t pass WACK at the moment’.

What exactly does this statement mean?

I’m sure it’s something obvious right?

A quick Google reveals that WACK stands for Windows App Certification Kit.

I’m guessing it means that Microsoft are in league with the devil and require you to write everything in C#, because they want to keep you on their side of the fence. Kind of like how Apple used to be (or still are?) about Objective-C, I think.