This is John Reinan’s weekly marketing column for MinnPost.com.

Is the laptop computer going the way of the desktop calculator? I just had an experience that made me feel pretty certain that it is.

I spent last week at a major building industry event, the International Builders Show in Orlando, for our client Marvin Windows and Doors. I packed a shoulder bag with all the usual gear of a traveling businessman: notebook, leather portfolio, laptop, power cords and chargers.

And in my shirt pocket I carried the iPhone that I bought about a month ago – an upgrade from the balky, early generation Samsung smartphone that I’d been using for several years.

About halfway through my four-day trip, I suddenly realized that I hadn’t touched my laptop. Hadn’t taken it out of the case, hadn’t turned it on – and hadn’t missed it a bit.

I was doing everything through my iPhone: e-mail, shooting photos and high-def video interviews, uploading items from the show to Marvin’s web feeds, writing blog posts for their media room. For many of you this may be old news, but for me, it was a revelation. My old phone was so difficult to use – both ergonomically and technologically – that I’d never really explored its capabilities.

(Although I did write the piece you’re reading on my laptop. Long-form writing is one area where the smartphone may never be the best option.)

In a recent MinnPost item, I cited an analyst’s prediction that smartphone sales will overtake sales of laptop and desktop computers by 2012. Now I understand that prediction more than ever.

However, the marketing industry as a whole is even more behind the curve than I was individually. Because another thing I’ve noticed in my brief time as a member of the mobile generation is that I’m seeing relatively few effective mobile interactions between companies and me as a potential consumer.

Of course, there are downloadable apps – tens of thousands of them. And I’ve used a few. But in spending hours a day using my smartphone, I was rarely exposed to an opportunity for any meaningful marketing interaction.

I don’t doubt that marketers will find ways to increase their connection to mobile consumers. There are a lot of very smart people in this industry working on that, and the potential rewards are huge for those who get it right.

But it may also turn out that the smartphone will settle into a role as a tool: an amazingly powerful and versatile tool, but one that offers fewer opportunities to engage consumers than marketers are currently anticipating.