I am building a blog aggregator like Techmeme that finds most popular posts from several blogs. Unlike Techmeme, first, I aggregate blog posts from a variety of RSS feeds, then save the headlines and relevant URLs in database. After that, I have to find what the most popular blog posts are.
For defining top blog post headlines, I track Facebook and Twitter share counts for every post of every blog and I rank the blog posts for their share counts. But that isn't the best solution because some bloggers can cheat via increasing their sharing counts with fraudulent shares.
So my question is what criterias could I use to define what the most popular posts are? What would be a better algorithm for ranking blog posts?