The latest announcement is now here, Be'Lakor the Dark Master is a digital release that adds a character to either your Warhammer Fantasy or 40k Games. For 40k, the rules inside the supplement are clear, that Be'Lakor can be used as an HQ for either a Chaos Space Marine or Chaos Daemons Army.
The image above is a released image from the Black Library and Games Workshop.
So yes, I went ahead and picked up the Dataslate (which is what they are calling this addition to the game), which adds just one character to the game. He is an expensive one though sitting at 350pts but really is quite strong for what he is.
He comes with Eternal Warrior, Psyker level 3, and Shadow Form (giving a 4+ invul and shrouded). However the most interesting thing about him, is that he just knows all the powers from the Telepathy discipline. Very cool. So no rolling for Invisibility, he just has it.
Overall I think this guy is very tough and can add a lot to your game. The 40k version is 16 pages long with some background information which I have not yet read. You can get the ebook version for $3.99 or the interactive one for $4.99 which is not bad. Slightly more than a cup of coffee at Starbucks.
So what does this dataslate do? It adds Belakor to any Chaos Daemon or Chaos Space Marine army as an HQ choice. Dataslates are defined on page 2 and 3 of the release, saying that "the unit can be used as part of any detachment that corresponds to the Faction listed on the datasheet". Faction being defined in the description as being a part of the codex (with examples listed)
You can look up and download a sample of the dataslate, or purchase it by following the link.
http://www.blacklibrary.com/games-workshop-digital-editions/Advent-2013
Note that you can buy Be'Lakor for either Fantasy or 40k, or get an edition that contains the rules for both games.
With this release, new possibilities are becoming available for new releases of characters or even new units. December is going to be a fun month.