Google Earth for the iPhone and iTouch has now been released and this is one amazing application. It integrates with things such as your contacts list. When I selected to search, and started to type my own address, my full address showed and I was able to just select it.
You zoom in/out using the usual pinch finger.
It was speedy using the WiFi connection. It includes the Panoramio and Wikipedia layers under the “Geographic Web” by default. Click on a blue photo icon when you see one, and it will load the Panoramio photo for that location.