Google Blogs (via Gizmodo) has announced that the long-rumored Geo-Location based services in Mobile Safari are indeed included in iPhone 3.0 and being put to use in "My Location" searches by Google.com on the iPhone.
As of today, when you visit www.google.com from Safari on your iPhone 3.0, you can choose to turn on My Location by tapping on the link on the homepage. When you tap on the "update" link, your location will be updated and displayed right there on the homepage. Whenever you want to refresh your location, just tap the "update" link. Testing this in New York, my search for "jazz clubs" returned a handful of places within walking distance. I picked one, tapped the phone number, made a reservation, and we were set for the night.
As to privacy concerns, Google stresses the service is opt-in and can be turned off via the Preferences link at the bottom of the page.
Good news for those looking for a local burger joint, bad news for those hoping Latitude wouldn't be stuck in the browser...