The game has been under development for some time at the previously PC-only studio - we'd heard on the grapevine months ago that it was working on an Xbox 360 game, which was obviously Halo Wars. As Bruce Shelley on Ensemble notes, "It's being played every day now and we are feeling very good about where it is and where it is going."
Shelley also confirms that Halo Wars is built specifically for 360 (although, as with Halo itself, PC gamers might get to enjoy a port in a few years), and that Halo creator Bungie is keeping a close eye on the game to keep it true to the Halo universe. In fact - you might want to save this one for a particularly geeky trivia competition - the original Halo design was for an RTS-style game, so in a way Halo Wars is going back to its roots.
Sadly, Shelley doesn't spill all on the fine details of the game, closing with, "This game has a long way to go before being published and we won't be getting into too many specifics about it for a while." You can be sure we'll be waiting patiently for those specifics, though.
October 4, 2006