Hi everyone. Few things here:
1) This update is basically reinstalling the whole game. This is due to the changes we made to data consolidation. It is replacing the old game files + adding Void Edge content. The game file size after the update will be smaller than the current one. You can see the before and after sizes here.
2) For people with 100GB updates: You most likely have the HD texture pack installed. Here is how to remove that. The update should be around 60 GB or so.