I'm also working on CImageGL which takes care of loading SDL_Surfaces and using them as OpenGL textures. Will be nice to be able to use SDL_image to load my textures without having to rely on something like libpng being installed on someone's computer or writing my own image loader. Got a prototype of the class working, just need to iron out a few wrinkles and it'll be done. It's also a bit easier to code as it doesn't need to have as many functions as CImage. I'll put it up when I get it done.
I'd like to eventually put a wrapper around more of the library, some things like SDL_Color could be really useful, maybe a class to draw geometric shapes too. But in the mean time i'm more interested in getting the GUI finished on my main project.
I suppose someone else probably has already written a c++ wrapper around SDL, a quick look around with google only came up with SDLmm, which looks like it hasn't been updated in 4 years. There's also a c++ wrapper in in the book Focus On SDL, but getting it to compile on linux hasn't worked so far (I haven't put much effort into figuring out what's wrong). Oh well at least it's something I don't mind reinventing the wheel for.