Dubbed glNext: The Future of High Performance Graphics, the presentation promises a "technical breakdown" of the new API along with "live demos of real-world applications running on glNext drivers and hardware." The teaser also claims glNext will be "the singular choice for developers who demand peak performance in their applications."
As we learned in August, glNext is an effort to rebuild OpenGL from the ground up as a low-overhead API. That focus isn't surprising given the direction AMD has gone with Mantle and the one Microsoft is pursuing with DirectX 12. However, it is a little unusual to see Valve taking a central role in presenting the new API. I wouldn't be surprised if SteamOS factored into things.
Valve developers Pierre-Loup Griffais and John McDonald will speak during the session along with Johan Andersson from the Frostbite team, Niklas Smedberg from Epic, Dan Baker from Oxide, and Aras Pranckevicius from Unity. So, six developers in total, divided by two from Valve, equals Half-Life 3 confirmed. Or something.