SDL 2.0 has been *officially* released. Along with it comes a new website!
http://www.libsdl.org/
Also, the documentation for SDL 2 has been completely re-done to be more complete and to fix mistakes (thanks to Ryan Gordon and Lantiga). Check it out.
EssGeEich, eh, I guess...? It's probably recommended to use it in conjunction with a rendering library or with OGL directly. It's incredibly easy to get a OGL context running (not sure about DirectX but probably just as easy if you figure out the details).
SDL 1.2 had experimental hardware accelerated renderers as well. The API didn't disallow it, it just wasn't as capable as the current API.
In addition, I see a lot of heat between SFML and SDL performance. This should be neglible (outside of perhaps event handling). If you were to make an indie game, you would absolutely never use the built-in rendering functionality of SFML since these functions use the absolute bare minimum of OpenGL to function (i.e. they're very, very slow compared to modern techniques).
Yeah, I saw that and was curious when it went stable. Apparently it went stable the first of this month. Learning SDL is on my TODO list so I'm looking forward to jumping into using it for something. Lazyfoo is a great source for learning SDL from what I have heard and if you are worried about what it can do I'd say quickly do his SDL1.2 tuts then jump straight to his SDL2 tuts to see what changes there are so the transition will be easier and not befuddle you.
I still don't get why you would actually need a tutorial. Most of his examples use blitting and repeat them selves and add per example, adding functionality from another subsection of SDL. Looks more like he's teaching you to program than how to use SDL.
What wouldn't you be able to figure out from the documentation?