After reviewing the 5 Firefox extensions for SEO, we find that there are basically two different categories of extensions: 1) one that adds SEO-related information to search results, and 2) one that shows SEO metrics for the page you are currently on. Extensions built by SEO Book and SEO Quake fall under the first category, and extensions built by Rank Quest, SearchStatus, and SEOpen fall under the second category.
Because the two categories of extensions are very different (first category is for people doing serious SEO research, second one is for people who are interested in the site they are looking at), I decided I will recommend one extension from each category:
Category 1: Adding SEO-related information to search results
I think both tools are excellent, as evident from both getting a total score of 25. SEO Book’s information on query terms is countered by SEO Quake’s ability to show information on the page you are visiting. At the end, the difference was that I just did not like SEO Quake’s display under the sponsored search section in the search results pages. Therefore, I will go with SEO Book’s tool.
Category 2: Showing SEO metrics for the pages you are currently on
For this category, the winner is SearchStatus. The fact that it shows the information at the status bar at the bottom of Firefox rather than eating up real estate by showing a toolbar is the differentiating factor.
I recommend that people use the extension from SEO Book for serious SEO research, and the extension from SearchStatus for getting SEO information for a particular site.