A new, unauthorized version of Windows 10 has leaked, but it's hard to tell whether Microsoft allowed the leak or not. In any case, build 9888, with a file name of JM1_CCSA_X64FRE_EN-US_DV5.iso or some variation, holds only minor changes.
The internal build number is 9888.0.amd64fre.fbl_release.141113-2137, which indicates that a partner -- likely a hardware manufacturer -- is responsible for leaking a build created on Nov. 13. You can bet the leaked bits are watermarked, and somebody at a partner site is currently drowning in deep duck dung.
If you go searching for the bits, verify them against these hashes:
Again: This is not an official Windows 10 Technical Preview build. It's a leaked, pirate version. There won't be a Windows blog explaining the high points. Gabe Aul won't tweet about it. If you install it, don't expect to be able to upgrade it in the future, and don't bother sending Windows Feedback.
Here's a brief overview of the changes from build 9879, which was the last official release.
There's a bit of new eye candy, with gliding animations for maximizing and restoring windows. Be still my beating heart.
Also, the Ver command and Help/About for certain apps reveals that Windows 10's reported version number is now 10. Peter Bright at Ars Technica has an excellent overview of how the historic discrepancy between the branded number and the version number stamped into the kernel works. Windows 10 previously reported that its version number was 6 or 6.4 to avoid breaking poorly written apps, unless the app specifically told Windows it understands how to handle newer versions.
There's nothing particularly earth-shattering about the change in version number.
The build 9879 zPC Settings Metro app -- which, in build 9879, appeared on the All Apps list -- has been absorbed into the main PC Settings Metro app, with the build 9888 version of the Metro app called simply Settings. The layout of the new Settings app is similar to the old zPC Settings, although there are significant differences in content -- the new Settings now has an Activate Windows pane, for example. Data Sense is gone in the 9888 version, as is Storage Sense. There are many more small changes.
Even in its new form, the Metro Settings app covers only a small percentage of all the tweaks available in the Control Panel. It's very much a work in progress.
The DockingController app, which was on the All Apps list in build 9879, doesn't appear in build 9888. That won't raise many eyebrows because it didn't work in build 9879.
Media Player doesn't appear in the All Apps list for build 9888. Windows still doesn't have double-click playing support for FLAC or MKV files, although they're both expected in the final version.
The build still identifies itself as a Windows Technical Preview, with no additional guiding light.
Running in build 9888, Windows Store reports that it has updates for 11 built-in apps, including Skype, OneNote, Music, and Mail, Calendar, and People. Running to the Windows Store in build 9879 doesn't reveal any such updates.
Anecdotally, it looks like 9888 is more stable than 9879. However, your mileage may vary wildly.
If you find anything else new, please drop a line in the comments.
Microsoft hasn't said anything to change our earlier understanding that there will be no more updates this year, but lots of goodies coming early next year.