Microsoft has begun rolling out the Windows Phone "Tango" update, or officially it is Windows Phone 7.5 Commercial Release 3 (CR3) -- according to a Technology Evangelist at Microsoft, who has received the update on his HTC Mozart, running build 7.10.8107 of Windows Phone 7.5.
The article claims, the update comes in three stages -- the update will first upgrade the phone to 7.10.8112.7, then subsequently updating the phone to 7.10.8773.98, and finally to build 7.10.8779.8 (or the standard Windows Phone "Tango").
The whole update only took a few minutes to download mostly due to the fact that "Tango" only offers a few fixes, updates to the OS (mostly around enhancing MMS), and minor performance improvement while launching applications.
Here are a couple more screens of the HTC Mozart Tango update:
No, word if HTC is pushing this out for other devices but the company has announced that it won't provide 'bootloader unlock' to HTC One X owners.
Back in July 2011, the company had announced of releasing bootloader unlock tool for a number of its devices -- followed by the release of 'bootloader unlock' on August 15, 2011 to HTC Sensation (EU). "The bootloader unloack basically allows owners of Android phones to load custom ROMs onto their phones in exchange for any warranty rights they may have been enjoying."
Here's the official word from HTC, according to MoDaCo:
HTC is committed to listening to users and delivering customer satisfaction. Since announcing our commitment to unlockable bootloaders, HTC has worked to enable our customers to unlock the bootloader on more than 45 devices over the past six months. In some cases, however, restrictions prevent certain devices from participating in our bootloader unlocking program. Rest assured, HTC is committed to assisting developers in unlocking bootloaders for HTC devices and we'll continue to unlock additional devices in the future.