Right, that's why nobody uses the iPod anymore. They all got bored and switched to SansDisks & Zunes -- "Not necessarily better, but different"...oh, wait...[People bored with RAZR]...
Now I'm not saying Apple is going the same route, but It's going to take more than adding 3G, GPS, and some colors to keep its customers when the other phones catch up (which they ALWAYS do). Apple's been smart so far, as people who are on other services haven't experienced the iPhone yet. What happens in 2 years when the AT&T exclusivity is up, and Apple (presumably) floods the market with iPhones? Once those contracts end (and other phones improvde), people are going to look for a different experience. Not necessarily better, but different.
Face it, comparing the iPhone to the Razr is ridiculous, the RAZR is just a dumb phone that makes phone calls -- the iPhone is a platform, a computer. In fact it would be much easier for someone to switch from a pre-iPod Touch iPod to another brand, than it will be from the iPhone/iPod Touch. People will have massive investments in apps, that will work nowhere else. And developers will have a massive investment in the iTunes App store, they are unlikely to go elsewhere.