You can see the leaked Grand Alliance Order book here.
Check out the links for additional images and details.
via Parodius on Warhammer Forum
Lady Atia has more additional information including what looks like a translation.
via Lady Atia
In the order grand alliance, fyreslayer, old dwarfes with warmachines.
Billions of men and women descendant of the old world resident.
Finally the mysterious aelves - very few but with a lot of magical knowledge and Monster they have learned to tame.
You already know about sylvaneth and stormcast, seraphon and fireslayer the book have all the warscroll plus a selection of formations.
But that is only the tip of the iceberg 280 - pages covering 16 old factions from : Devoted (fantatics), free people milicia, Battlemage, 10 aelves faction, Darkling covens, phoenix temple. Even if the elves are in order alliance they follow mysterious ways and are an autonomous force. And the Ironweld arsenal - human canons and duardin steam-engines ....
Also Next weeks hints
"The Realmgate Wars continue in Beastly Fashion!"