In recent days, we’ve been discussing Twitter authority and tracking people in the public eye such as Diddy (@iamdiddy) and John Mayer (@johncmayer) reaching out to the masses via Twitter.

Many celebrities have established their Twitter Persona and actively engage, as we see on blogs such as Celebrity Tweet which give a real time feed on celebs like Solange Knowles (@solangeknowles), Ryan Seacrest (@ryanseacrest), Britney Spears (@britneyspears) and Greg Grunberg (@greggrunberg), who all have jumped on the Twitter bandwagon.

While many of these people in the public eye have already embraced their inner geek, many are just getting started with establishing their profiles.  And then there are those celebrities who are using their voice and influence to promote others’ — the Twitter Influencers.  As word of mouth marketers, we’re obsessed with the power of the shout out and its influence on the Twitter population we like to call Tweeps.

Take the recent Jimmy Fallon experiment as an example.  A few nights ago, Jimmy’s guest was Bryan Brinkman (@bryanbrinkman), who had 7 total followers on Twitter. After the shout out from Jimmy (and the founders of Digg also appearing on the show), Bryan now has almost 35,000 followers, and growing by the hour.  The shout out was then featured, written about and syndicated on blogs and sites (like this very one) which continues the shout out momentum.

Another great example is Ellen DeGeneres who talked about Twitter on her show very recently. The day her show’s Twitter profile @theellenshow was launched, there were just a little over 9,000 followers.  She now has over 200,000, growing rapidly.

While most of us aren’t able to appear on television to get the official shout out to spread the word about our Twitter presence, the power of influential bloggers is not to be underestimated as a way to grow your Twitter audience.  Mashable, a highly influential blog in the social media space regularly features people to follow in several verticals, ranging from Professors to Brands and the People Behind Them.  It’s safe to say that this blog drove a few followers to those profiles.  Ok, maybe more than a few.

We’ll be keeping our eye on the Twitter Influencers and paying attention to the power of the shout out.