I started using RankIQ when it launched a few months ago, and have been loving the analyzer tool that helps you know exactly which important words (dozens of them - not just 1 or 2 keywords) appear in the best content on google's top results for your target keyword. The tool analyzes your actual blog post and gives suggestions for words to add. This is super valuable for me in writing and updating old content to make sure I'm producing content that is on par and beyond with what google already ranks. I love how straightforward it is. Review collected by and hosted on G2.com.

The keyword libraries are less valuable to me, personally, because I do all of my keyword research on a different tool, plus my niche isn't totally covered yet. (Although they're frequently adding more.) It is fascinating to look through the ones they do have, though, and I gleaned a few great ideas for new content. Review collected by and hosted on G2.com.