Well, after publishing it in the Plugins, you will want to have at least two articles on your site with the same keyword (in Metadata Information -> Keywords). The plugin will then appear on those articles.
As an alternative solution, I was thinking maybe it would make sense to implement the feature similar to what The Economist has for user comments (pls see
expandable Reader’s comments in the bottom
www.economist.com/business/displaystory.cfm?story_id=13381522
). Similar approach is used by mXcomment extension for Joomla.
This would reduce JoomlaComment’s size at the bottom of the page and would allow publishing other plugins without losing users’ attention.