We’ve all heard the news… twitter is “in”. And universities and colleges are no exception to the mass of brands, users and organizations jumping on the 140-character bandwagon. In the last 6 months, there has been a massive uptake in university twitter use, with admissions and marketing people leading the charge.

But a recent Nielson report on twitter reveals that the twitter population skews heavily in the direction of over-25-year-olds, with teens making up less than 16% of the twitterverse. While many argue this will change, and soon, and I do believe that it will, eventually, this fact still brings up a very important question.

Why are universities on twitter?

I ask this because as administrators, admissions personnel, marketing and PR people and alumni relations managers flock to twitter, they are ignoring other much larger populations of online interaction. The answer lies, in part, because these people understand twitter better than they understand other networks. Why? Because they all fall in the right demographic for twitter! We all would prefer to use tools and techniques we can relate to, understand and can use effectively. Broadly speaking, the university personnel to whom we refer fall directly in the target demographic for twitter use.

This is not to say that using twitter can’t be useful to colleges and universities. But I do think we need to do a better job of understanding the audience on twitter and catering communication effectively. For example, planning an alumni engagement strategy on twitter is a great direction to move in. Your target group is older, more likely to engage on twitter, and less likely to be consistently getting information about the school from other places.

Attempting to use twitter to grow enrollment? Probably not the best plan. Using twitter to reach currently enrolled students? Don’t count on major uptake in that area. Does that mean you’ll have to go back to using the old tools? Definitely not! Teens and early 20s adults are online constantly, usually in places like Facebook and MySpace, and are connecting with the community in ways that can be incredibly valuable for universities and colleges. We just have to build more strategy around how we communicate in different channels and understand where our target groups are interacting, not just which tool seems the best to us!

For more information, check out Mashable’s take on teens and twitter, they have some useful general info on what user groups are growing and interacting there today.