I doubt we preview the other before the 0.8 release. It's just not got enough done compared to this one. Aymar just went on an incredible tear and suddenly this faction's unit side was too good not to preview. The other will be in 0.8, but just not as ready. By 0.9 or 1.0, you'll probably get a more full "preview" of it, as their best units get more complete, but you'll know who they are by then.