If these stats don't rock your world then maybe you should get out of marketing

 Believe me when I say that vast slices of your market are in here.

 Facebook: Over 200 million members and 80 billion monthly page views (Techcrunch)

Twitter: It now has over 44 Million unique visitors a month (according to Comscore)

YouTube: Over 100 Million visitors in March and over 13.8 Billion video views in

March alone (YouTube report)  

LinkedIn: Over 16 million unique visitors a month with a a very affluent demographic where the average user is 39 and makes $139K ayear and over 500,000 C-level members (Quantcast)

MySpace: Just under 100 million visitors a month and 43 billion page views (Techcrunch)

Digg: More traffic than the New York Times with 23 million unique visitors a month and 4.5 billion pages views (Techcrunch)

Blogs: Over 5 million blogs are tracked by Technorati, the “Bible” of Blogs with 600,000 being corporate blogs (Technorati)

Wikipedia: Nearly 63 Million Unique visitors June 2009 (Compete)