... except they've repeated time and time again (most recently from Scotty) that Kahn is NOT in this movie.
I'm going to go out on a limb here and say that JJ, inspired by having seen Generations for the first time, decides to put half the crew in the 09 movie uniforms and the other half in these new uniforms. Then, in Trek 3, the uniforms will be different again (though with some similarity with the new Trek 2 uniforms).
Also, the addition of more lens flairs, cowbell and, by popular request, the addition of a Dharma logo.