Social Media in an Orwellian world

In his classic novel "1984", Georges Orwell presented a dystopian world where everyone was watch at all time by the all knowing Big Brother. This entity controlled the though of all citizen ensuring the good of the society.
The witty writer would have marvel at the social media networks and ubiquity of surveillance in our world. All for the sake of security, all major communications an social tools are subjected to government "spying". The government does not intervene as strongly as in the novel, still it is scary to see how our information can be use against the population. 
Often more aggressive than governments are the corporations that profile online users to present the best marketing strategy. Just by looking at the "likes" of someone on Facebook, it is possible to deduce some personality traits. From there a marketer can build a solid profile by looking at the purchases made, items searched in the last month, etc.
With almost every online activities logged, what your are looking for can easily be determined. The catch is that almost everyone willingly grant access to all that information. No one is forced to "post", "search", "like", etc. online. We do it to be part of something bigger. To be recognized by our peers, to be "in". And quite often we like having the right advertisement at the right time. Who cares how they guessed what I need if it save me the hassle of searching.