Given the obvious success of the HH models, books and novels, and GW themselves jumping in with two board games, it can only be a matter of time before HH starts to shift more and more towards GW. I can see this going as far as the normal relationship between GW and FW: GW owns the core game and models, FW make the more extravagant extras and upgrades.

The recent significant price drop in FW's HH book collections could also be an early indication: maybe FW is clearing their warehouse so GW can take over printing responsibilites in a second edition HH game? I can see that happening after the rumoured 8th ed 40k hits, with GW then printing supplement books to play Age of Darkness games.

All that being said though: I hope it doesn't change significantly from the way it is now. Cheap plastics to form the core of your armies, with FW taking the brunt of everything else for the HH. The books are absolutely gorgeous and I wouldn't want that to change. I also wouldn't want the game to change significantly, with its focus on more faithful representations of the legions and a focus on "fluffy" and "hobby" armies.