Actually, any service out there that tries to do away with the requirement that people actively perform some effort would fit the bill for a potential Google ki

Actually, any service out there that tries to do away with the requirement that people actively perform some effort would fit the bill for a potential Google killer in a particular vertical. In other words, any recommendation service that preferably can "learn" the habits of its users and then simply recommend new content. DirectedEdge is just the latest player in this game. I personally track the news recommendation niche. There used to be a service called Findory that in my opinion came very close to being "optimal". But they went under for some reason. The closest to Findory (and with some very cool features such as computational lie detector for news) is http://www.euraeka.com http://www.euraeka.com They have all three basic features - search (aka Google-style), discovery (aka crowd-wisdom style) and recommendation engine.