If you have any kind of email list (subscribers to your e-newsletter, for example) there is a great (but not free) tool for you. Flowtown lets you upload your lists and then lets you know where each person is on social media. So, for example, you can learn that 90 percent of your contacts use Facebook, while only 10 percent use Twitter.
Flowtown digs deeper to offer influencer ratings for your contacts. Who has the most influence on Facebook, Twitter, etc. This could help any communicator find your product evangelists and who can help you gain traction at social sites.
You can set up an account for free, but the service is not free. You can go so far as to upload your contacts and see some insights without paying, but the service without paying is very limited.
I would love to hear from any of you that use this tool. Any feedback on whether it is worth the investment?
Just wanted to get this option on your radar. Hope you find it interesting.