Indian naked female archers heh, guess that's their main selling argument ;)
Still, I don't expect anything much from this. It probably won't even get us a new patch for RTW (and we all know the vanilla campaign quality).
If you want to know what I think, it's highly probable that this is some old content one or two of CA's guys made in the beginning and didn't finish which SEGA took and wants to make a bit of money with now.