A Tool to Track Popularity in the Blogosphere Blogpulse, an incredible piece of software for the web, tracks 9.5 million blogs online through RSS and scraping and culls a repository of monthly and daily data for each term mentioned by the bloggers. It is able to highlight trends, make comparisons and illustrate term popularity with remarkable accuracy.

The best part is that this incredible software is completely free for users to try out. The graph on the right shows my own sample which measured the terms "Search Engine Optimization" vs. "Search Engine Marketing" vs. "Search Engine Rankings". They are labeled accordingly, SEO, SEM & SER.