I've been watching a live video feed at iPhoneLaunchTV. Just a bunch of NY guys drinking beer, playing with their new iPhone, skyping with folks around the world.
Supposedly, the had an Apple employee call in to answer some questions, and he had some interesting answers. First, this first version of the iPhone doesn't have 3G because it wasn't considered as pervasive in the US as it is in Europe. There have been other reports about size and battery life considerations. I guess they would never say that this is what AT&T wanted.
GPS might be implemented in the future via triangulation. Flash may also find its way into the iPhone in the future.
Regarding the slowness of EDGE, the Apple guy suggested that you use Wi-Fi for Google Maps, and then when you're away from the hotspot, you could just refer back to what's in your cache. I don't think the use of Wi-Fi is really emphasized in the demonstration videos I've been seeing. I would think that this would really sap battery life.
Finally, this chap said that there are various prototypes the Apple is working on, to try out 3G, and other add-ons, possibly for the next version, possibly for other markets such as Europe.