Some took this to mean the end of traditional GPS devices. In an analysis of "What the iPhone 3G Needs to Put Garmin and TomTom Out of the GPS Business," Popular Mechanics suggests that Apple merely needs to "mold a piece a plastic to a suction cup" to make the iPhone 3G your go-to GPS device.

PC World was a tad less enthusiastic, saying that "the real killer app for GPS continues to be turn-by-turn driving directions, of the sort that companies such as Tom Tom and TeleNav make possible on other GPS-enabled phones."  In other words, the current Apple software, although a giant leap, will require third-party support. 

And, according to Reuters, Tom Tom, one of the GPS heavies, apparently already has a navigation application ready to go.

So what does this mean for the traveler?   Beyond a demonstration of GPS, yesterday's keynote featured a location-based social networking application that allows for users to determine the location of others in the network.  A little scary!  But this has applications for group travel as well as other uses. Imagine getting lost in Madrid and saying "Ayudeme!" to the iPhone-equipped staff at your hotel.  Other applications in the works include interactive city guides.

And GPS gives people an excuse to use the iPhone's built-in--yet mediocre--camera.  Every photo can be geo-tagged with the exact location of the shot.

Will the iPhone 3G's GPS capabilities make it the de-facto device for moderately tech-savvy travelers?  It's yet to be seen.  But if the company's past expertise in user-friendly interface can be taken into account, Apple may do to GPS what it did to music players, phones, and the personal computer. 

Of course Google is currently developing its own operating system for mobile phones. We can expect they may have a bit more to say on this subject as well.