Before I get too far into this: I always used to use the example of Asia being so far ahead of us in cellular technology with the example of location-based buddy proximity because I had seen an example of it 3 years ago on the internet. My starting point was to tell people to imagine that they had a lunch appointment and they had received permission from the person that they were having lunch with to see that person's location. If you know exactly where that person is, then you don't need a call or text if they are running late, if they are right outside, if they are circling looking for a parking place, etc. because you can see what's happening. Inevitably they would ask we we don't have the phones and I would explain that it's a network problem: Asia has a single network standard, which makes it easy to upgrade and even easier to adopt higher speed protocols. The uniform network standard enables the phone manufacturers to focus on development of the device functionality as opposed to network operation. Then that functionality allows the software developers to develop cool uses for the functionality.
Ok, so now I have to get a new example of how Asian networks are insanely ahead of us, but back to Latitude.
I would love to tell you that I've already used Latitude and that it is awesome and great and is already changing my life, but unfortunately it's not available for the iPhone. Presumably it will be available only when Apple releases the next iPhone firmware update as I further presume that there needs to be an upgrade to the core Google Maps application on the iPhone.
For those of you that can use it (Nokia, BlackBerry, WinMo), Latitude seems like the must-download application of the day.