Another vote for the young and interested: I'm 25, taught US History for 11th graders, and this is VERY big news to me. I don't watch TV, hardly read internet news, but just the announcement itself caught my attention (I don't care for hype). When I hear "Deep Throat" I always think of Watergate first, Linda Lovelace several seconds later... (since I was waaaay more interested in history than porn up until the last 6 months or so!).
If you don't care about this topic, then you must have been stoned during US History in high school and college... I don't care if this broke 50 years after the fact, or 100.. it's STILL big news.
EDIT: Let me add that my 14 year old cousin is currently reading All the President's Men, and he is very into it. I don't care what age you are, you'd better damn well know your history, and know how important it is.