Wow, it does really seem quite possible at this point. i'm quite surprised. I would of thought they would of just done a release akin to that tyranid one last year and just had updated rules in a campaign book or something - but it really looks like they might get a whole new codex. I still clearly remember the current/last one like it was yesterday.
I wonder if they will remove Harlequins now they are their own "army" ?