Another option that doesn't seem to have been mentioned, which might work if you are writing multiple-POV-character fiction, is to switch viewpoint characters between chapters and let each writer "own" one or more of the viewpoint characters. As long as you have a reasonably firm outline, this allows each author to work relatively freely, and in such a case the differences in style may actually add to the flavor of the overall story.
This works best if the characters don't partake in each others' activities too much, but with a shared reasonably solid understanding of the characters among all authors and some editing it may very well work well enough even if the characters intermingle.
Viewpoint character switches can get confusing if done wrong, but of the books I've read, I believe the ones that switch viewpoint character at chapter boundaries have all worked well. Of course you may need a solid round of editing at the end to bring everything together and make sure the story is consistent, but that is probably a good idea anyway so all things considered is probably not a huge drawback.