Congrats on the raise :) I just tried Prismatic, and while it seems interesting I don't think I would become a regular user. Though I may not the target audience. I'm usually satisfied with Hacker News and The NY Times, though occasionally I'll look at other mainstream news sites like CNN to make sure that I'm getting a well rounded idea of what's going on in the world. I have Reddit blocked on my computer, but I'll…
Agree, but let me ask you this. Do you want a personalized news feed of only things you are interested in? They are working on making that and I'm not aware of anyone else trying. It's not there yet but I like the idea.
Thus, personalizing my news by auto-subscribing me to sub-categories that the system "thinks" I'm interested in doesn't really solve any problems that I have.
The harder problem of news, in my opinion, is determining what's important and interesting and what's not. Time-weighted voting systems like on HN and Reddit do this very effectively. For example, I am generally more interested in the "Most Popular" articles on NY Times than whatever the editors chose to put on the front page.
I would be more interested in a startup that tried to create a HN for another vertical, like the movie industry.