I have a little theory:  Every person is an aggregator, collecting and passing along certain specific subsets of information for their own enjoyment and for the potential benefit of their readers/listeners. 

The internet is one giant aggregator.  It gathers information about everything and displays it for people to find, read, watch, and listen to.  Any website that collects and shares links (which is pretty much every website) is an aggregator.  Boing Boing collects and distributes "wonderful things".  Kottke finds and shares "fine hypertext products".  Lifehacker, Consumerist, Neatorama, TechCrunch.  All these websites collect information about particular topics and subjects and pass everything on to interested readers. 

The news industry is the same.  CNN has people that look for newsworthy stories covering a range of topics.  Similarly, the job of the local sports writer is to find information about local sports and pass it on to his/her readers.  It's all about collecting and distributing, gathering and passing on. 

In the same way, people are aggregators.  Everyone has their own personal interests and hobbies.  Some people collect and distribute information about politics.  Some people do it with jokes.  Some people know everything about Apple products, and their knowledge gets distributed as desired (and sometimes when not desired).  Essentially, anyone who has conversations is an aggregator of sorts.  They know some facts or opinions about certain topics, and they share these facts and opinions with other people in the form of speech.  If you watch the news, read the newspaper, read the comics, read magazines, read books, watch TV, watch movies, or do anything else that consists of gaining information with the possibility of passing that information on to someone else, you're essentially an aggregator. #psychology