I'm a long-time Treo/Palm smartphone user who didn't like the direction Palm is heading (toilet), but wasn't willing to smoke the Apple crack. The Droid came along at just the right time for me. I got one for my wife as well, since she was just starting to look at GPS devices.
I'm a linux software developer by profession. I also work with a greyhound rescue that has me out doing charity work, but still need internet access. Which is why I've always had a smart phone.
I'll probably end up doing some dev work on the android platform. It looks intriguing to me.