As you are all aware Jervis dropped a nugget or two at the Chicago Gamesday recently, discussing Necrons amongst other things. [as reported on BoLS]
-The Studio loves the idea of Chaos Legion specific codices. It will allow GW to build Legion specific models, but is still a while off.
-Necrons are further along that that, and Mike (???, unclear) has been dropping hints of what we may see in an upcoming Necron codex in various books."
From the Gamesday thread, reposted in an attempt to kick start this discussion away from the distort of all of the other gamesday rumours and notices.