A series of leaked screenshots allegedly from a confidential Valve PowerPoint presentation show the company's Source 2.0 engine in action. The images were posted by reputable Neogaf user "CBOAT" which gives them a bit more credibility if nothing else.
What we have here is an updated version of the Plantation level from the Left 4 Dead 2 campaign Swamp Fever. As you can see, the screenshots demonstrate the increase in detail that is possible with the Source 2 engine which includes enhanced foliage, improved lighting and shadow effects, among other things.
Elsewhere, one of the slides outlines some of the redesigned tools and workflow of the engine. Some of the slide is cut off but what we can see discusses a powerful GUI front end for content authoring that can be extended with custom and pre-game assets, a browser for quickly finding, managing and editing assets and automatic compiling of content.
We've known for some time now that Valve has been working on a follow-up to the original Source engine a CEO Gabe Newell revealed as much back in 2012. At the time, he said Valve would launch the engine when they had a promising enough game for it.
There are no hints as to what that debut game might be but I imagine most are crossing their fingers for Half Life 3. Other options could include Left 4 Dead 3 or perhaps even a completely new series but with any luck, we'll see the engine debut sometime this year.