iPhone 2.2 is available and one of the cool features is the Street View in Google Maps. To see the Street View go to Google maps, allow maps to use your current GPS location, drop a pin, then select the little human figure.
These are screenshots of the Google Street View near my house that Google Maps provided by using my iPhone's GPS location. Using the iPhone you can rotate the picture 360 degrees with your finger. This would be useful if you were walking around a neighborhood. It's a little creepy...but still cool.
If you click on Street View in this Google Map it gives you an idea of what you see on the iPhone in street view, if you click inside the picture and pan around. I emailed myself this location from my phone and I wasn't outside so the GPS location isn't as accurate as it would be if I was outside...but it's close.
Besides Street View there are quite a few other Google Mobile - iPhone applications including Google Earth which has been available for the iPhone for about a month now. It's fun to play with. There is also the free 1-800-GOOG-411 that allows you to call Google to find the number of the nearest pizza delivery place (or whatever you are looking for).
I haven't got the Google Mobile App for iPhone with Voice Search down yet - I asked for "cheeseburger" and Google thought I said "Missouri" but I think that might be a result of my poor diction rather than a fault of the voice recognition software.
This is a screen shot of the Google Mobile Applications from my iPhone. It's actually two screen shots that I pasted together because you have to scroll down on the phone to see them all.
Google Voice Search uses the accelerometer in the phone to detect when you have moved the phone to your ear and then makes a little beep sound to let you know it's time to say what you are looking for.
If you say "pizza" it tells you the address of the nearest locations and gives you the option of calling them by pressing an icon.
In general I'd say the iPhone is really fun for anyone who likes playing with tech stuff and most of the interfaces are really simple which makes it appealing to people with a low tolerance for gadgets that require reading a lot of instructions.