The mystery of Windows 8's new 'Protogon' file system

Here's a Windows 8 feature about which I haven't heard before: A possible new file system known as "Protogon."

Windows enthusiast Sandro Villinger has a nice summary of some of the known and unknown Windows 8 features that various folks have discovered since internal "milestone" builds began leaking over the past couple of months.

Villinger makes a passing mention of something I hadn't heard of in his Windows 8 Top 10:  Something named (or codenamed) "Protogon."

From his May 31 IT World article:

"I've also dug up traces of some underlying file system changes that I couldn't quite make sense of, such as an entirely new file system driver called "NT Protogon FS driver", which looks like a kernel mode driver for some sort of (yet unknown) file system called Protogon. It's unclear, whether this is a major new file system or just some minor subsystem."

I asked Rafael Rivera of "WithinWindows" fame as to whether he'd heard of Protogon. He did a quick check and said that whatever Protogon is, it  seems to incorporate database-like concepts like transactions, cursors, rows and tables. He said it includes a string, which seems to indicate Protogon could replace or at least emulate NTFS (the NT file system) as needed. Rivera also wondered if Protogon might be an update of the "Jet Blue" file system/extensible storage engine adapted for the latest version of Active Directory and Exchange Server.

There were a lot of rumors early on about Windows 8, including that it might have a brand-new file system. Now I'm wondering what this thing really is. WinFS revisited? (WinFS was a new storage engine that was supposed to be part of Windows Vista, but which was largely shelved, save some concepts that went to the SQL team.)

I doubt we'll hear anything about Protogon during Windows Chief Steven Sinofsky's appearance at the AllThingsD conference on Wednesday. (Sinofsky may show off the Windows 8 interface for tablets, according to rumors and reports.)

Windows 8 is expected to be released to manufacturing in 2012 (in spite of any/all official retractions you may read about).

Anyone have any guesses (educated or not) about Protogon?