like I said, not a genius, just a geek
those would be primary, with the other standard subcategories, followed by pairings categories. so, there would be an AU section for each primary category. There are also multi age stories (which would also span the books), so I'm thinking there should be something to allow for that as well ANYWAY.
Something I've noticed looking through the LotR book section here, is that there are fics that actually belong in the movie section. As we all know, there was a great deal of deviation from book to movie. Combination of characters, elimination of character, twisting of and addition of events (like the Battle of Helm's Deep, no elves in that battle but for Legolas), skipping of entire segments (Tom Bombadil and the Barrowwights come to mind there).
I ramble though...it'll be nice to be able to eventually have all that sorted out where it actually belongs as well.