Harnessing Social Networking Contexts

I was in my car driving home and pretending to know the lyrics to a song Ive heard a million times when the thought dawned on me. How many times have I heard this song and I still dont know the lyrics? Then I thought well its probably cause I can sing along well enough without actually memorizing every word and fake the ones I dont remember by predicting the word based on the context of the song. This led me to another thought on how cool would it be to write a program that could predict the next word to a song. So I started thinking you could mathematically eliminate words based on the last word and choose the next from the leftover possibilities and the probability based on language structures. For example nouns followed by a verb and so on... And it amazed me on how fast the brain is able to do this. In a fraction of a second our brains can deduce a very small set of possible words. Sometimes we are right and sometimes we are wrong but more often than not you are going to be pretty close. Why is this? Given our brains are more adept to parellel processing is a huge advantage but I think more importantly in terms of output we are able to inject more percise contexts. We understand what the song is about and others like it. We understand the artist. We understand mood.
Where am I going with all this? How does it relate to Social Networking? Well Im not entirely sure. My thoughts on this are still premature but I think its very interesting and worth discussing. So heres what Im thinking. Social Networking allows people to interact with each other and eventually find others of like mind to share ideas and express themselves. From this like minded set of individuals groups usually form which therefore creates a context. This group defines its own context from which one could if understanding this context predict what sort of events may occur in this group. One could determine a lot about an individual using the contexts of the groups they may belong.
What does this contextual information mean? How can it be harnessed? This is what Im trying to answer. Other than the obvious linking people together based on preferences lets dig deeper into this phenomenon of Social Networking. Can I use these contexts to determine the lyrics to a song or more importantly stop a terrorist attack. This may be a stretch but can these contexts be used to predict the future. Could these Social Networks be used to process data in a distributed/parallel fashion. Who knows?