Like many in this forum, I encountered the gamesave corruption problem (with Mercenary Pack), though only AFTER I got an update this morning. The first time I encountered it, I loaded up an earlier savegame and kept playing.
Now, at 26 hours of gameplay, it's shredding EVERY gamesave I try to load -- that is, I encountered the error loading the most recent save, then tried to load the previous savegame, then the one previous to that... and it's crashing/shredding on ALL of them (and saying my hard drive is unavailable). I've stopped trying, but I've already erased a few hours of gameplay.
This is a gamekilling bug. Shame on Obsidian for not testing the game and DLC properly before release. I can tolerate game crashes and graphics foibles, but not this.