It watches the chan for anyone who posts a github link, and informs the chan of the details of that repo. So if one of my devs says "Guys we should use this instead of Step for flow control: https://github.com/substack/node-seq
", Toady would inform the room that it's a popular library but hasn't been maintained since October of 2011 despite a number of issues being logged against it.
Nothing you couldn't figure out by clicking the link and looking around for 10 seconds, but this way, your channel works for you instead of the other way around. The whole room sees the info at the same time, so no one gets lost in the ensuing conversation.