Information ranking based on social media

Importance ranking of webpages was suggested to be more and more based on "social signals". I.e. how often is a webpage shared rather than linked. But this raises questions like: will the importance given to a shared piece of information differ by the "social" status of the person who shares it? I.e. is some link shared by Barack Obama "more worth" than some link shared by me? If so, who decides who is "more trustworthy"? These questions haven't been answered. However google & co. started implementing this kind of social ranking already. If you have a g+ account and you do a google search, eventually you will find "personal search results", based on the things shared by people you have in your circles. And to be honest, this service is amazingly useless at this stage. Let's say I perform a google search "android tablet". Most likely I am looking for some product information about android tablets or some wikipedia entry or whatever general information. However, the "personal result" only seems to perform a full-text search over all the posts of the people I follow on g+. A full-text search...that's it? Is this supposed to be the new awesome world of social ranking? There is no useful information in the 110 personal results whatsoever, since most people mention the terms "android" and "table" in a rather specific content: either they are talking about an app or a special feature of some android tablet or the success of android tablets in general or ... In this respect the "social signals" are not used in a constructive manner - they just add more clutter to the other 530.000 search results. The challenge will be to add a useful social dimension to improve information filtering. And I feel we are far away from that. Something else is needed here.