The Motrin incident (USA Today article)  that unfolded over the weekend reinforces a fundamental dimension of the entire social media phenomenon: If people care enough about something, they’ll make the time to engage in the communities and conversations where people are talking about it.

This is nothing unique to social media. A typical person, in addition to the hours he or she devotes to work, will hit the links for 18 holes with friends, get out to a PTA meeting, go to church on Sunday, attend a neighborhood activist meeting, take a night class, attend a chapter meeting of their professional association, chat with family on the phone, chat some more with neighbors over the backyard fence, and go out to a sports bar to watch a ballgame with the gang.

While some people try to cram too much activity into too little time, they deal with it by missing a meeting or skipping church one Sunday to sleep in a few extra hours. They don’t crash. That is, they don’t just stop all their activities. But for some reason, there’s a pervasive belief among many that this is exactly what’s going to happen in the online space. As Steve Rubel put it in a post back on June 11 last year:

We are reaching a point where the number of inputs we have as individuals is beginning to exceed what we are capable as humans of managing. The demands for our attention are becoming so great, and the problem so widespread, that it will cause people to crash and curtail these drains. Human attention does not obey Moore’s Law.

Steve added this past April…

By 2009, the Radicati Group predicts that we???ll spend 41% of our time managing email. Now add to that the IMs, documents, Facebook pokes, RSS feeds, Twitter tweets and text messages coming at us and we???re officially way oversubscribed…Unfortunately, the problem will not abate. Human attention is finite. It doesn???t scale. Worse, the pace of change today is so rapid there???s a huge need to stay digitally savvy.

While email overload certainly is an issue, it doesn’t plague people who simply don’t use it, which includes a huge slice of those under, say, 25 years old. My daughter, who’s nearly 20, doesn’t list email among the tools she uses, and when I remind her that I know she has an email account because I use it to send her email, she responds, “I know. That’s why I have an email account.”

As we move to other channels, email is taking a back seat. The vast majority of email I receive is made up of mostly newsletters to which I subscribe. If I don’t have time to read them, I don’t read them. Those that look interesting get shoved into a folder I open when I have time, mostly on planes. But much of my interpersonal communication has shifted elsewhere, including Twitter, Facebook, and Skype IM, each of which is more effective than email at what I’m using them for. I other words, I’m reallocating my attention to better channels. And I’m not alone.

Nobody is forced to respond to Facebook pokes any more than they’re required to avail themselves of every conversation at a cocktail party. (I have never sent one or responded to one, and I don’t feel like my Facebook experience has been diminished one iota.) RSS feeds allow you to consume more information in less time—not the other way around—and text messages take a lot less time than email (a quick question gets a quick answer and I’m done).

People will avail themselves of the communities and tools that interest them, fuel their interests, feed their passions…just as the MotrinMoms did. Many of those participating in that conversation may have felt like they already had plenty of information coming their way, but I doubt any of them felt that keeping up with the hashtag and blog posts and YouTube videos was an additional burden weighing them down.

Anybody who feels compelled to engage with everything all the time probably is dealing more with a personal addiction issue than a simple excess of inputs. (In case you hadn’t heard, China has codified Internet Addiction Disorder as a legitimate diagnosis.)

Just as we make time for the interactions and communities that satisfy and define us in the real world, we’ll do the same online as the Net becomes the new commons. I just don’t believe there’s any great attention crash on the horizon.