Kristian: No this changes nothing. Activision owned Sierra before this and that won't change just because there has been a change in Activision-Blizzard's ownership.
LiquidOxygen80: Thanks for the reply. I couldn't remember who came first, Activision or Vivendi.
Your confusion is understandable as there are actually two companies that had "Vivendi" as part of their name(The one originally owned by the other). So basically Vivendi had a gaming division called Vivendi Universal Games, VU Games for short. They owned Sierra and all its properties. They happened to buy Blizzard as well. Later they changed their name to just Vivendi Games. I am not quie sure where that fits in to the timeline. Anyway they then merged with Activision. However the deal was structured such that all of Vivendi Games, EXCEPT Blizzard Entertainment became part of Activision Publishing Inc. Both Activision Publishing Inc and Blizzard Entertainment Inc became wholly owned subsidiaries of Activision Blizzard Inc with Vivendi as its majority owner.
Subsequent to this Acitivision Publishing sold some of the assets of Vivendi Games and merged others into various existing Activision subsidiaries. In the process Vivendi Games ceased to exist as an entity. This is how Activision Publishing Inc came to own all of Sierra's properties.
Recently a deal was entered into were Activision Blizzard Inc bought a chunck of its own shares from Vivendi, while a team led by among others Activision Blizzard CEO Bobby Kotick bought another chunck of Activision Blizzard shares from Vivendi. Vivendi still has shares in Activision Blizzard but now they are just a minority owner. What it is they are a minority owner in, is that same thing they were a majority owner in. This includes the Sierra properties(via Activision Publishing Inc). Activision Publishing Inc and Blizzard Entertainment Inc are still wholly owned subsidiaries of Activision Blizzard Inc.