Pew Internet & American Life Project released a new study on the use of Twitter in 2012.
Here is the summary directly from their website:
What is surprising to me is that Twitter is far from being a mainstream social networking service. 15% of online adults use Twitter and only 8% on a daily basis. In comparison, 65% of online adults use social networking sites such as Facebook, MySpace, or LinkedIn. It shows that Twitter is still a niche service and I can report that most of my students – current and future government leaders – have a very difficult time to get on Twitter, to be part of the conversation, or to find valuable information.
Another surprising fact from the Pew studies is that there does not seem to be an increase in the use of Twitter over the years: A 2010 study reported the same number – 8% of online adults were using Twitter two years ago. This is the same number as in 2012. Interesting!