This week Valve published an update regarding its plans for the 2.0 version of its SteamVR Tracking tech, detailing the ordering process for licensees and informing them of some significant changes to the system.
Most notably, Valve intends to update the new base stations sometime next year so they can work together in groups of 4, covering a play space of up to 10 x 10 meters.
That's a significant improvement over SteamVR Tracking's current 2-base station maximum, which tends to max out at a play space of roughly 4 x 4 meters.
This puts a hard number on Valve's previously-stated plans to improve and expand the number of base stations supported by SteamVR Tracking, but it's not a hard stop -- the company goes on to note that it is looking at supporting even more base stations, though it won't say when or if that will happen.
This is presumably possible because the new SteamVR Tracking 2.0 base stations are capable of providing data when hit with a tracking laser. That data can identify where the laser is coming from, which allows the system to work with more than 2 base stations.
VR devs should also know that the new SteamVR Tracking 2.0 base stations will begin shipping to licensees early next year, and won't work with earlier versions of the system -- most notably, current HTC Vive headsets.
They also won't ship with any sort of mounting equipment, since Valve is "creating a custom wall/ceiling mounting solution" it expects to talk about next year.