You know you've established your brand when its name becomes a verb (for example to 'Google' something). A company called PostRank might hope the same holds true for adjectives, as in "What's your PostRank?" The company hosts an ingenious service that tracks the millions of Web postings that appear every day and ranks them based on the tweets, Diggs, reddits, and other linkback activities that follow.

These activities, which the company refers to as "engagements," are a better indicator of the value of a piece, according to PostRank co-founder and VP of development Jim Murphy. "We're looking at what people do, as opposed to what people say. And that's an important difference," he said in a phone interview yesterday. "We're not asking you what is good or bad content--and to vote up or down. If I use delicious, where I'll save a bookmark that I want to refer to later, we record that as an interesting engagement." PostRank has agreements with 18 major social networks, and looking to add all the time, Murphy said.

Founded in 2007 as AideRSS, the company started by developing a way to qualify the huge number of articles fed into RSS readers every day. "The engagement generated by each story has a ranking function that we plug into [RSS] readers. So of these 500 themes, which generate let's say 700 or 800 stories a day, [we present] the 50 you really need to look at," based on how many other people have thought enough of the piece to spread the word. "Don't read every story that's published, just read what matters and what is generating a lot of conversations." The free service is available now.

Last month the company unveiled PostRank Analytics, a fee-based service that resells its engagement data "out the back door to news aggregators, marketing and PR companies and everybody you can imagine," as Murphy put it. A Youtube video shows you how it works. In essence, the service lets you track, in real time, who's clicking on (thanks to a link with Google Analytics), linking to, commenting on and tweeting about your postings. You can even drill down to the individual users and contact them directly. "When you're publishing a story, you're not necessarily trying to convince people to buy a book, download a white paper or do anything. Instead you're tying to figure out what is resonating--which topics, authors and tone--and who's in your audience, how are they responding."