Nine days ago, some Lumia 650 owners found that there was new firmware waiting for them through the Windows Device Recovery Tool. The icing on the cake was that the update would enable the coveted double-tap to wake feature.
Four days later, users started seeing over-the-air updates. It also became apparent that firmware with the same version number was rolling out to Lumia 550 devices, but without double-tap to wake.
For a time, it was a mystery as to what was included in the update, but today, Microsoft has finally published a changelog. Here's what's new in firmware version 01078.00042.16352.50xxx:
Support for double tap to wake enabled for Lumia 650.
Wi-Fi connectivity improvements, including fixes for Wi-Fi connection dropping randomly and Wi-Fi scan occasionally not returning any results.
Bluetooth connectivity improvements.
Stability and reliability improvements.
Camera improvements, including improved image and video quality, improved Auto-focus and fix for a problem that was causing slow motion capture to skip frames for some users.
Cellular connectivity improvements, including fix for a problem that caused occasional network loss for some users.
Audio quality improvements, including fix for a problem that caused voice call audio to get scrambled for some users.
Some had speculated that the update was similar to the one that enabled double-tap to wake on the Lumia 950 and 950 XL. Those people were correct, as the release notes are identical, with the exception of the note about the Lumia 650 at the top; in fact, they could have been copied and pasted, to use an example of just how similar they are.
If you don't have the new update available just yet, be patient. Firmware updates are tailored to each device, which comes down to your region and carrier variant, so it will show up on different phones at different times.
