I commented :
Surely it depends if Facebook succeed in getting people to tag (or classify) their social links.
There are ways to do this on FB, but it doesn't promote it much. But someone could write an app. which could somehow classify the relationship between two people based on things you tell it, even what your interests are etc. Then it could export that knowledge to widgets on the Engadget site.
Why not even make this a query option on the widget : "show me things that work-colleagues like", or "show me things that geek buddies like" or even "show me places that friends with higher than 85% similarity to me on the RockYou survey of "best things to do on my day off" like"