Back in the internet boom at the turn of the century, one of the popular debates was whether the internet would provide exciting new access to a diverse range of information or whether the internet’s ability to give you far more power over what information you see or read would result in a narrowing of horizons as people just go for what they already know and what they already agree with.

Cass Sunstein in particular made the case for that latter pessimistic view very forcefully in his Republic.com book and it’s a pattern you see often in, for example, choices over political blog readership where supporters of different parties particularly congregate on blogs that take similar lines.

Now, however, researchers have taken a close look at how news is shared on Twitter and come up with a rather more positive finding:

Indirect media exposure [i.e. people seeing stories shared by those they follow on Twitter] increases the diversity of political opinions seen by users: between 60-98% of the users who directly followed media sources with only a single political leaning (left, right, or center) are indirectly exposedto media sources with a different political leaning. In orderto reach this conclusion, we use public classification of news sources and infer the political preference of every audience member. One can only speculate about the effect of political diversity, because users do not necessarily read the complete Twitter timeline nor do they always prefer receiving diverse political opinions (Munson and Resnick 2010). Nonetheless our results show the power of social media, in that users are exposed to information they did not know they were interested in, serendipitously.

One of their other findings is that for all Twitter’s newness, the sources of information are mainly fairly traditional:

There is much about the media landscape in Twitter that is ‘old media’. Established media outlets retain the role of publishing news and stories without much interaction with readers. However, the features of the ‘new media’ age are reflected in the way journalists and audience engage in new communication patterns, communicating with each other directly, and tapping into breaking news.

Media Landscaipe in Twitter – A World of New Conventions and Political Diversity