Fascinating report out of Comscore on Twitter's demographic breakdown:

18-24 year olds, the traditional social media early adopters, are actually 12 percent less likely than average to visit Twitter (Index of 88). It is the 25-54 year old crowd that is actually driving this trend. More specifically, 45-54 year olds are 36 percent more likely than average to visit Twitter, making them the highest indexing age group, followed by 25-34 year olds, who are 30 percent more likely.

twitter-comscore I expected the lower trending for the under-25 crowd as that demographic grew up on Facebook and lives there. I would have expected that the 25-34 bracket would be Twitter's sweet spot - always online, early adopters and followers of pop-culture. But the 45-54 bracket is surprising... until you consider that marketers and companies indeed represent a significant portion of Twitter:

With so many businesses using Twitter, along with the first generations of Internet users “growing up” and comfortable with technology, this is a sign that the traditional early adopter model might need to be revisited.