It's possible they changed some of them, but I doubt they're random seeing as how I've ran the same dungeons since patch and find the same extracts in them every time; e.g. If I run a dungeon that drops Pasus I'll never see anything other than Pasus.
Edit: Okay, now I see they are actually randomized. Before must've been total coincidence that I was getting the exact same extracts every time.
Edit: Okay, now I see they are actually randomized. Before must've been total coincidence that I was getting the exact same extracts every time.

