HTC One (M8) owners, as there is no need to wait for the official Android 5.0 Lollipop build to hit your handset over the air. The ever-restless developers over at the XDA community have hammered out a custom ROM for the One (M8), presumably based on leaked GPe edition of Android 5.0.
Needles to say, you have to get the bootloader unlocked, and have some experience with installing custom ROMs, but if you want to be an early adopter, that's the price to pay, and it is not all that intimidating to begin with.
Since the ROM is based on purportedly leaked official GPe version for the One (M8), you can rest assured that the Duo Camera tricks and other HTC-specific shenanigans are working, though some users are reporting minor issues with this SkyDragon ROM, which will hopefully be ironed out soon.
In the meantime, HTC's Mo Versi said on Twitter that the official Lollipop update for the Google Play edition devices will start as soon as next week, so not much to wait either way.