...is apparently the replacement name for metro apps, said in response to Tom Warren's (The Verge) question during "The principles of Microsoft design" session.
I guess we're back to Microsoft Design Language Framework 2012-esque names?
I do find it interesting that it's "Windows 8" and not just "Windows" since the number is dropped in future versions.
EDIT: (see below) It's actually Windows Store Apps. No "8".