One of the negative impacts is that social networking has contributed to a downward slope in communication skills. As this article shows, various factors involved in social network communication are having a negative impact on people's communication skills. For example the amount restriction of characters forcing us to express ourselves in as few words as possible, or the option to edit our comments diminishing spontaneity.
Following the same concept of the last article, this one expands on the negative impact social media has specifically in communication between teenagers. While teenagers spend more and more time chatting through computers or cell phones, face to face conversation are becoming less common loosing quality real time, face to face interaction.
This link refers to these social network relationships as 'electronic relationships' and states they're not the same as real relationships, affecting our ability to differ for example acquaintances and genuine friendships.
This link deals with "social network addiction" explaining the amount of time we are putting into social networking, and most important of all, the dependency we're acquiring to it, can compare to that of a drug addict to its respective drug.
Another example of the negative impact of communication through social media can be seen in this article by the BBC about the recent England Riots. As social media can reach masses in a fast manner, social networks were used to organize riots which ended in wreckage of property and injuries.
Another, much talked about, impact social media has on society is the breach of privacy.
This link explains hows coorporate espionage in India through social media, is used by corporations to gain an advantage over their competitors, and also spying their employees through social networking websites.
Even the way employers go about the process of adding employees to their companies is changing. As seen in this article on ABC, job hunters are stalked on social media, some saying networking sites like Facebook have cost them their job.
This article on Forbes Magazine, shows that Facebook's privacy issues are deeper than we know making much of our information public for anyone to see.
This link analyses the inappropriate use of collected information from social media applications.
This interesting article on The Atlantic Magazine, goes into yet another way social media can be used to control society, showing how the CIA uses social media to track how people feel.