An excellent research application, Social Technographics, that emerged from Forrester's research and analysis that led to the book Groundswell. The approach breaks down the audience in social media across age, gender and geography to offer a sense for how folks interact in the social space.
For much of the emergence of social media, the majority aside from early adopters were observers - who followed, read and watched as the "conversation" driven by blogs, Facebook, Twitter, LinkedIn and many other outlets swelled to millions of users. More recently there has been a shift to perhaps not publishing content, but adding their own voice to the conversations.
Recently I watched a presentation where McDonalds was cited as affirming their chief of social media was the customer. The retail outlets have proven they can experiment in social networking and generate revenue with a relatively low investment expense to adopt tools or platforms. As social media, guidelines and solutions for compliance emerge and mature in financial services, it will become more and more a standard to have social media as a channel for your marketing and communications, interactions with customers and the public and more.
While many advisors I speak with suggest they have a client base that is weighted more toward retirees and is not relevant - I always ask - "are you going out of business in the next 5-7 years?" and "do you need to continue establishing your brand publicly for the next generation of investors?". If they answer yes to one or more of those questions - they need to explore social media.