"Top 6 viewed question on Q2A"
Yeah, it's a shame that too many Q2A site operators are so focused on being SEO whores, rather than seeking plugins that provide functionality to benefit their site's USERS.
A few months ago, Google announced that it will cease passing plaintext search terms in the referer header and/or querystring... reputedly with intent to enhance user privacy. As a webmaster, if you want the referer info from google, you will be forced to use GWT (google webmaster tools) along with (perhaps) GoogleAnal-licktics
So, in the absence of google passing plaintext qs searchterms, is the proposed module "worth it"? It could still capture/display inbound search terms for searches refered from Bling and Yahoohaw... but those probably represent only 18%--30% of the total inbounds.
All said, I'm skeptical that displaying the inbounds "serves to increase keyword density and... improves SEO". In fact, recognizing it for what it is (SE spamming) I suspect its inclusion might invoke a google ranking PENALTY.