An interesting visualization of Twitter as 100 people is a good take on a popular infographic meme, but reveals a few inconvenient truths about these sorts of images.
Firstly, although I am (not so) secretly pleased to see this illustration of Twitter's non-inclusive communicative nature let's not forget that Twitter, like so many other social phenomena, follows a power law distribution. We've all heard a lot about the "long tail" - here it is in action.
Second, "100 people" visualizations, or any display of percentages, need to have exclusive categories to work well; otherwise they may not add up to 100%. In this case, are the "5 loud mouths" really different people from the 5 with more than 100 followers? And couldn't one of the users with many followers also be a lazy account? These overlaps create issues in the discrete presentation of demographic groups. If the groups really are exclusive - which in this case would have to be by chance rather than by design - then the graphic works well.
Finally, more of a nitpick than anything else: if Twitter were a community of 100 people, then how could anyone have more than 100 followers? Obviously, the number refers to the true Twitter population, but it's incongruous with the graphic. One option is to scale 100 people down to this sub-community, but then the figure would lose its impact, for the scaled version of 100 users would be just .0024 (based on a true population of 4,200,000 Twitter users). A second option is to abandon the "100 people" metaphor and go with a percentage-based pie chart, but that would ruin the appeal of the infographic.
For a truly excellent set of "100 people" visualizations, see Toby Ng's collection.