Amazing stuff going on at the mod nexus. We already have new clothes, some of them made with new models. Right now we have almost 80 mods, which is much more than most of the games on the site. Great things are about to come
Stuff like new models are certainly possible: I've done a few bits and pieces myself, though some of the stuff that's been uploaded is just as-yet-unused models from the game files, so there's a risk that people may see the same stuff appear in the full release and bits of it need fixing. But that's the nature of mods and nobody goes into it with their eyes closed. Well okay, most don't!
I would imagine that the official situation remains unchanged, and there's pretty much no chance that the modding toolkit will make an appearance before the actual release but it'll be worth me checking in periodically to see when mods can be "supported" on the forums.