Windows 8: Beta collectors waiting with bated breath for a leak

While there have been various minor Windows 8 leaks claimed and reported by various sites, Microsoft has kept a tight lid on its next version of Windows to date.
But in the past few days, rumors of a possible leak of one of the newer Windows 8 internal builds have been gaining steam. Some known beta-leaking sites have been posting new screen shots of what they are claiming to be leaked Windows 8 builds. These builds may be from one or more select OEMs, who supposedly are finally starting to get private test builds of Windows 8 from Microsoft.
There have been all kinds of claims as to how and why Microsoft has managed to keep Windows 8 leaks to a minimum. There’s a forbidding warning (beyond the milder “sssh. let’s not leak our hard work”) on the alleged Windows 8 screen shots. It reads:

“Unauthorized use or disclosure in any manner may result in disciplinary action up to and including termination of employment (in the case of employees), termination of an assignment or contract (in the case of contingent staff), and potential civil and criminal liability.”

There also have been claims that Microsoft has coded identifying information into Windows 8 downloads to help the company track leakers. (One of my sources said that there are some builds of Windows 8 that are “Red Pill,” which means they only can be downloaded by certain individuals when they are on the Microsoft campus.)
The latest alleged Windows 8 screen shots don’t sport the new Windows 8 user interface(s), as the interface typically is one of the last pieces that Microsoft adds to Windows test builds. (I am using interface in the plural here because we Microsoft watchers have heard there will likely be at least two different interfaces for Windows 8 client when it ships, with one being a tile-based touch-centric one, known as MoSH, for Modern Shell.)
On March 30, a bunch of new alleged Windows 8 screen shots, posted by CNBeta.com, make mention of a possible new Windows 8 feature known as “History Vault.” The WinRumors.com site described History Vault as Microsoft’s answer to Apple’s Time Machine. History Vault, from what little can be gleaned from the new screen shots, looks to be an update to Microsoft’s Shadow Copy feature that has been in Windows since Vista.
Other recent alleged Windows 8 screen shots have shown the “System Reset” capability that Microsoft told OEMs in April 2010 that it planned to add to the coming version of Windows. Some sites also claim that there are mentions of Internet Explorer 10 in some recent Windows 8 builds. In April 2010, Microsoft was telling OEMs that IE 9 would be the version of IE that would be included in Windows 8. My deduction: The IE team has decided to get the lead out, and is on a faster turn-around schedule than expected just a year ago.
Microsoft developers are working on M3, or Milestone 3, of Windows 8 at this point in time. Once M3 is done, which should/could be this summer, Microsoft is expected to make test builds of Windows 8 somewhat more widely available. I’ve heard from a couple of my contacts that Microsoft could show off Windows 8 to its partners at the Microsoft Worldwide Partner Conference in July in Los Angeles, if not before. And last I heard, the Softies are still planning to hold a Professional Developers Conference (PDC) in September (most likely in Redmond), and plan to make available around that time either a Community Test Preview or possibly a beta of Windows 8.
Apologies for all the “allegeds” and “supposeds” in this post. Microsoft officials still are not talking about Windows 8, and — believe it or not — still not confirming officially that the next version of Windows will be “Windows 8.”