With the 1.0 release of the OpenXR 1.0 specification, Collabora have begun to detail more work going on with Monado their open source OpenXR runtime for Linux.
As a quick reminder on Monado (source):
At the center of Monado is a fully open source OpenXR runtime for Linux. It is the component in the XR software stack that implements the hardware support, it knows how to process non standard input from HMD devices and controllers, it knows how to render to those devices and it provides this functionality via the standard OpenXR API.
Before getting too excited, they make it pretty clear in the latest update (posted a few days ago) that Monado isn't quite ready yet, with "many pieces missing". They've invited anyone adventurous to join their IRC or Discord.
As for work being done, they've made improvements to the OpenXR state-tracker, making it more complete and getting it closer to conformance. They still have more work to do, including "code to handle rebindings of actions to various hardware". They've merged in four new drivers to work with PSVR for the HMD, PS Move Controller driver, OSVR HDK driver and the Razer Hydra tracked controller driver.
As for what else is to come, they say the biggest chunk of their work is going to be tracking, with two main types to deal with including "outside-in where sensors in the world track an object, and inside-out where sensors in the object track landmarks in the world (this is a gross simplification)". They're focusing first on "outside-in color based tracking system" with the PSVR, to help with their goal of being maker/hacking friendly. I suppose it helps that PSVR compared with other VR systems, has a pretty low cost.
Find the full post with all the technical details here.