New PCGamer online article

http://www.pcgamer.com/total-war-warhammer-2-brings-high-fantasy-to-a-redesigned-campaign/

Some notes:

High Elf leader Tyrion begins in Ulthuan, for example, while his brother Teclis starts in Lustria

new Vampire Counts sub-faction located in Lustria

independent forces called rogue armies now roam the map. Each rogue army is a bespoke force built around a theme that ignores faction restrictions—one example CA provides is a goblin beastmaster who commands a combined force of squigs, wolves, spiders and dinosaurs

And lots of other details that weren't in the magazine scans I've seen.