Summer is upon us -- millions of kids are being unchained from school this week -- and that means vacation season is about to begin in earnest.

And here's a tip: Resist the urge to Twitter your vacation plans to the world, no matter how awesome they might be.

USA Today is warning about the very real danger of using Twitter as a surrogate for sending postcards to your friends and family, as the service broadcasts to anyone with a computer the obvious fact that you're not at home. In the case of Israel Hyman, he tweeted about his plans to leave town, an impending 10-hour drive, and his safe arrival at his destination far away from Mesa, Arizona.

You can see where this is going: When the Hymans returned home, Israel discovered his high-end video editing equipment had been stolen. His best guess: Those ill-reasoned tweets offered the burglars all the opportunity and information they needed to do the job -- in real-time, no less.

Why single out Twitter rather than another social network? Because, by default, anything you say on Twitter is broadcast to everyone, not just friends who are following you. In fact, Twitter missives are searchable and updated continuously: A simple search for the term "vacation" on the site reveals numerous tweets about people planning trips, often with surprisingly detailed itineraries. (That's one I picked out at random in the image above.) From there is simple to find a user's full name, and a web search can often turn up their address, too, assuming the crook doesn't already have that information.

In contrast, status updates on a service like Facebook aren't quite as readily available to people who aren't your "friends" on the site, but, as many people accept a wide net of friend requests from people they don't really know, posting vacation plans on Facebook can be just as dangerous, as can automatic email responses telling anyone who bothers to drop you a line that you're out of the country.

While the real risk of tweeting about vacation plans is probably small, it's still a serious one that isn't really worth taking. Some options: If you have a small base of Twitter followers and tend to know them all personally, set your account to "Protect my updates" under the Settings function if you're determined to tweet vacation plans.

Same goes for Facebook and MySpace: You might want to make your Profile visible only to friends if a lot of information on your wall is too revealing of your privacy but you trust your friends not to kick in the door to your house.

But really: My best advise is to think about using all of these social networks after you get home. People would rather see your awesome vacation photos than hear about your grueling drive to get there, anyway.