Twitter, the microblogging service that allows users to post short status messages about themselves for people "following" them, has found its way onto the Web browsers and mobile phones of tech geeks all around the world. While I'm a fan and user of the service, I've come to believe there is very little chance it will catch on with a mainstream audience as a standalone application.

And it has nothing to do with the technology or the frequent outages the service has experienced. In fact, I like Twitter, the technology and the people behind it. I've interviewed its bright founder, Jack Dorsey, for CIO's "Five Things I've Learned" series. He talked about the power of brevity, and the idea that email and other technologies are failing us because they rely on too much crap being inputted each time you want to communicate (to field, cc field, subject field, body, text, spell check, send, and so on).

I wrote another story about how companies could look at Twitter's technology and apply it internally to streamline their own processes. Practicing what I preach, I use the service quite a bit. I've gained more than 100 followers and posted 500 or so updates (something power users and Twitter evangelists would surely gawk at as puny, but that is a whole other issue entirely.)

The barriers to Twitter going mainstream, instead, are two-fold: one is the existing user base and how they've come to dominate the site with their own obsessions/passions about social media, technology, and Twitter itself, making it less palatable for a new user who doesn't really care about those things. And two, the underestimation by these same folks that people are going to continue to be more open and social without any sort of regard for their own privacy and personal affairs (which would be a central issue for a site dedicated to "what are you doing?").

My brother, a finance analyst, made me see this reality recently over beers at our favorite pizza place. He is no Luddite (very wired, as a matter of fact), but he prevents me from getting over-excited about emerging technologies on the Web. He put it plainly:

"Why would I want people knowing what I'm doing on any given moment on any given day?"

It's question I'd heard before, especially when on the road attending conference sessions about the service. My response was pretty typical of a social media cheerleader:

"First of all, people are being more social and willing to share. And we're headed towards a point in time where most of the content and communications we engage in are inherently social rather than hierarchal. In other words, I'm going to be more interested in what you and our friends are doing and what you're reading than what some CEO or newspaper says I should be reading or thinking about."