This is just whizzing along now. :)
That's a Nintendo Switch running SDL's "testsprite2" program. It doesn't look like much, but if you can see that, a few things are true: we can draw on the screen, obviously, and OpenGL works. SDL's simple rendering API is up and running, too.
What you can't see in this video is that SDL's new Vulkan support works, too: you can create an SDL_WINDOW_VULKAN window and draw into it just the same as you can do SDL_WINDOW_OPENGL.
And, naturally, OpenGL ES is available, too. You can also work directly with the "official" Nintendo rendering API, but why would you do that? :)
Next up is getting input from the controllers and the touch screen. Then maybe porting something to it for fun.
A few other developers with devkits are starting to pull in this work, so I would expect to see some initial screenshots of other games popping up sooner than later, in any case.