The new iPhone will let you broadcast your location to people through a program called Loopt. And because this phone is now just 200 bucks, it'll finally become an industry standard instead of a fringe geek toy. So get ready for the biggest annoying shift in your social life since Facebook, because Loopt is about to do for the world what a little site called Dodgeball did for the Gawker crowd in 2004.

Dodgeball was like Twitter, only instead of saying what you were doing you said where you were. Basically any time you went to a bar or restaurant, you could tell all your friends through Dodgeball, and they could come hang out with you.

The site caught on among Gawker employees, like half of whom are friends of friends with Dodgeball founder Dennis Crowley. It also took over a group of techies in San Francisco, a group I joined in early 2006 that included dot-commers, Apple employees, and bloggers.

These crowds aren't just early adopters, they particularly love social technology — anything you can overshare on. So everyone was everyone's Dodgeball buddy, and the site upended our social dynamic. One night, two people Dodgeballing from a bar drew a crowd of thirty. I used Dodgeball to get a ride home when I got mugged.

I also found weird emergent behavior. For example, I wouldn't just keep track of my friends — I kept tabs on my frenemies, so I could more easily avoid them. Crowley supposedly checked in from false locations to keep people off his trail. Friends would get deeply insulted if they were taken off a notification list, and god did the parties get awkward when one person realized they were the only one not getting a text message when their friend walked in the room. I hooked up with a girl because she shoved her phone in my face, showing a friend-of-friend alert from Dodgeball, and said "Is this you?"

Okay, this was just a group of geeks, but that doesn't mean this behavior won't go mainstream. We've learned that from Facebook and (to a lesser extent) Twitter. So why is the iPhone the thing that'll do it?

Like I said, there's the price: The iPhone is now a reasonably affordable phone with a growing user base. It's as cheap as an iPod was when that blew up.

There's Apple's desire to change customer behavior, pushing technological advantages to the public that previously would only attract tech geeks. The iPhone makes people behave differently: They're more apt to pull up web pages (iPhone users download five times the data of normal AT&T users), they treat texts like IM chats, and now they'll assume everyone knows where everyone is.

And maybe, there's Loopt cashing in on this promise by marketing its service and pushing out all competitors. Who knows if they will? Dodgeball just didn't catch on fast enough, and maybe it wasn't just because it required users to remember to text out every time they went to a bar. Maybe it will get hype — like the excited New York Times piece predicting Dodgeball would be the next Friendster — but not major acceptance. Maybe people aren't ready (and some people never will be) to tell everyone where they are. But Facebook and Twitter have already expanded people's view of what's worth sharing with friends, and I think all Loopt has to do is equate itself with the concept of "checking in" from a place. Just like Facebook took over the idea of having an online analogue to your real-world life, and Twitter owns the idea of microblogging (even though dozens of other services have tried and failed to compete).

So what does Loopt do? Same as Dodgeball and Twitter: Say where you are, what you're doing, maybe send a photo. It's a lot of the stuff other sites already do, with the added benefit of pinning all the activity to a place. The company is pitching it as a way to know where your friends are, as often as possible. It will become normal to know, at a glance, where the people you know are. Here's their demo from this morning:

One emergent behavior I expect is the ultra-documented party. Bad enough with camera phones and blogging, but right now if I want to find party photos I need to search around. With Loopt I'll just check everything that happened at one bar on one night.

Has someone ever thought it'd be cute to "stalk" you with a few cameraphone shots on Flickr? (I have!) That'll get a little creepier when they're sending your exact location to the web in real-time.

You know too much about reporter-socialite Julia Allison? Well you're about to know HOW MUCH FUN she's having at that TOTALLY AWESOME PARTY with her CLOSE CLOSE FRIEND MARY. And you'll know it's all happening six blocks away.

And eventually, if you're caught going out for a drink without inviting all your friends, some lonely acquaintance of yours is going to bug you about why they weren't part of the group. Thanks a lot Apple.