In the tech industry it has almost become embarrassing to voice concerns about erosion of personal privacy. After all, it’s no longer a social norm, right?

In this brave new world that Facebook, Twitter, and Foursquare hath wrought, privacy is often seen as an outdated concern. People who speak out to the contrary are branded as Luddites or dinosaurs because, apparently, the future is already written and is already here.

But a funny thing happened on the way to the overmind. Google launched a little thing called “Buzz”.

Suddenly, privacy is alive again. I can’t even keep up with all the articles bemoaning this latest violation of our souls. The backlash has been quick and it has been brutal. Google has moved quickly and impressively to correct, but the damage is done. And in recent days the outcry has moved beyond Buzz to target location-based services like Latitude, Foursquare and Gowalla.

So which is it? Is privacy pointless and dead or alive and kicking? What’s going on here?

In a nutshell, we’re seeing that everyone cares about privacy…eventually.My hypothesis is that everyone has their own “privacy threshold” which is directly tied to how much they have to lose and how obviously those things are threatened. With Buzz, Google created a situation that triggered both of those alarms at the same time, for a huge number of people and at a very low threshold.

Don’t think you have much to lose? Don’t feel like it’s threatened yet? Just wait a little longer.

When we’re younger, we simply don’t have a lot of history. Our tracks in the snow are few and our impact on the world has been limited (unless you’re Mozart or Wesley Crusher). In short, we either don’t have a lot of “life data" or we haven’t yet realized that we value it. We therefore have less to lose if that data is used in ways we weren’t expecting.

Things change as time goes by. The more stuff we do (e.g. the more we “live”), the more life data we accrue. We build history, relationships, possessions, opinions, accomplishments and failures. We each accrue different life data at different rates, so it’s more about our personal experiences than it is about our physical age. The more life data we’ve accrued, the more we have to lose when that data is misused.

Many people claim that privacy is a generational concern that will soon be irrelevant. And I certainly concede that the “social norms” have changed. But my point is that privacy is not generational but rather is driven by life experience. Even today’s generation will start caring about privacy at some point.

When Google launched Buzz as an integrated part of Gmail, they linked it to what is for many people — regardless of life experience — a significant repository of accrued life data, and one that is assumed to be private. Email brings with it certain assumptions, but Buzz violated those in unexpected but immediately obvious ways.

As a result the Buzz launch became one of the most easily recognizable and least expected erosions of online privacy to date. It’s no wonder the backlash has been so severe: Buzz showed a huge number of people just how much they have to lose and clearly illustrated the immediacy of the threat.

But it’s not all bad news.

Personally I think this fiasco has done a tremendous favor for both the public and the industry. It has woken up a new set of users to the consequences of privacy erosion. And it has put some of today’s hottest tech companies on notice that this is something they need to get smarter about. I think we’ll ultimately see better, safer products and wider adoption as a result.

And that’s something to buzz about.