I liked most of this comment I found:
Actually, the only way you can form a truly meaningful social relationship with another IS through face-to-face contact. Humans, like many other animals, have [s]evolved[/s] as contextual creatures and require aural, visual, and tactile stimuli in order to accurately assess others and understand their intentions. Just as languages are more rapidly and faithfully assimilated by immersion, human interaction is significantly enhanced by the ability to judge facial cues, body language, and tonality in order to determine the veracity of another's words or the subtle thoughts they may have that they don't openly articulate.
In social contexts, people are not judged on the merit of their inner thoughts, but rather than the merit of their actions. It follows that the only way to truly ever know someone else is to observe their reactions to varying situations/challenges/rewards over a period of time and to draw conclusions about their personality traits. By robbing people of context, remote social interaction only allows people to see or hear others in a very narrow, controlled manner that relies on each individual to present themselves in an accurate and honest fashion. While you may be able to form seemingly close bonds/friendships with a person based on the limited interactions you observe online, those bonds will never be as meaningful or truthful as when the interaction occurs face-to-face and you can determine how authentic they are.
That’s not to say that there’s anything wrong with having acquaintances, online or offline, but if someone relies entirely on sites like Twitter to determine the quality of their social life and interpersonal interactions, then they are significantly starving themselves of healthy, meaningful human relationships.
BTW, I only use Facebook and Twitter to help me to qualify for online giveaways. ;D ;D