With 0% being "I've already played the full game" and 100% being "I haven't seen any media or read any info."
I'd put myself at 80%. I've played the beta twice, know the names and requirements of most of the weapons, spells and covenants, and know the names of about 3 or 4 non-beta bosses. But I've avoided streams and trailers though, as well as any story/NPC/enemy/area spoilers. As far as visual knowledge of the game outside of the beta area, I essentially know nothing.
I know a little about the classes and the covenants, that's it. Watched about 30 seconds of some dude chillin looking at some waves. Super proud of myself I actually made it this long without spoiling most of the game.
Now I just have to resist looking anything up if I get stuck because it just snowballs from there.
PSN: TMAN2626, Deprived and proud! "I mock your value system, and you look foolish in the eyes of others."
Guess I'm 90%. Played the Network Test and have kept up with most gameplay mechanics, but have avoided all story spoilers as well as covenant spoilers. The only things I've spoiled for were the number of weapons in my favorite weapon class (which I regret, it dulls the mystery) and the name of 1 boss.