The term collective consciousness refers to the condition of the subject within the whole of society, and how any given individual comes to view herself as a part of any given group.
One of the consequences of social media is the opportunity for large numbers of people throughout the world to come together, at least online, to collectively agree or disagree about something. Whether this is actively a “consciousness” is probably less likely. But certainly larger numbers of people quickly and collectively agree about many things that would, otherwise, take longer to develop a consensus.
In the cult movie, Close Encounters of a Third Kind, selective groups of people in different parts of the world simultaneously become affected by a single phenonenon that eventually leads them to mutually act without any obvious, common leadership. Although a work of science fiction, it does suggest the potential power of collective consciousness toward an inspired purpose.
These possibilities are a bit more fanciful than the current (2013) purposes for social media. I would suggest that the evolution of more lofty purposes for the instant communication and potential consensus building of social media is possible. I would also suggest that those of us who are developing New Media consider the possibilities and act toward developing opportunities for insightful, paradigm-shifting events.
Best Wishes for a Happy New Year in 2013.