I bought JV-relatives (and also JV-contentlinks) for our sites and since then, we've had great results in search engine ranking and our bounce rate has gone donw.
Because these two components makes it visibly very easy for the users to read other parts of the site.
When you're reading one article, JV-relatives shows the users, like, 10 other exciting articles and many people do read on.
This makes your usres happier, Google-bot sees your bouncerate is going down and thus gives you better rankings because you have proved to Google, that your site has great content (if not, the bouncerater would be higher)!
The support for this component is fantastic - Vinjay does a GREAT job and responds in a polite and nice way!
I really support the JV-components and plugins!