While Oculus Rift grabbed the most headlines with its revised Crystal Cove headset, boasting improved camera-based tracking and high-speed OLED display panels, other companies pledged to jump on the virtual reality bandwagon at the event. Biggest of these was Sony, upgrading its range of head-mounted displays to include head-tracking in the HMZ-T3Q which was demonstrated without, sadly, information on availability or pricing.All the hardware in the world is no good without software, of course, and it's here that Valve comes in. Having worked closely with Oculus Rift, the company plans to release a software development kit (SDK) designed to bridge the gap between varying types of virtual reality headset and the software being displayed - providing game developers with, hopefully, an easier way of adding support for various devices to their titles. Providing, that is, they integrate them with Valve's Steam digital distribution platform.While Valve itself has made no formal announcement on the matter, designer Brian Coomer told the BBC that the VR SDK will be released at the Steam Dev Days conference on the 14th of January.