Social media and promotion

A friend wrote a comment to one of my blog posts from the other day that got me thinking about maximizing your impact with the tools that are available in this new, somewhat anti-social, social (media) era.

He gave me an example of an author who had started out in a different field and then leveraged the followers that he achieved from that towards his new writing endeavor. I see a lot of examples of this online, in one form or another. People like Wil Wheaton, Neal Patrick Harris, Xeni Jardin and Joe Hill have all created careers by starting in one area and then easily porting their fanbase over to their new endeavors. Not to sound too much like an old man, but ten years ago, this would have been a task that required tons of PR and marketing help from outside agencies. Even in the case where it's not too much of a change, like from graphic novels to regular novels, it would have been more of a challenge. I'm sure some of those folks still have PR and marketing assistance but the amount they manage on their own has definitely increased with the advent of Facebook and Twitter.

And that brings me to my question for the week...

If you're involved with promoting something, whether it's a hobby, your blog, a product or service for the company that you work for, how have you had the most success building up your followers? Do you use different strategies to gain followers? What do you do to cut through the noise?